Download CCG Errata v5.0 - CPM Student Guidebook

Errata for Core Connections Geometry
The following changes have been made to Version 5.0 of the Core Connections Geometry text for books
printed after 01/2014.
Changes to the Teacher Version:
Problem Number and
Description of Change
Page
Number
Date
4
6/13/14
Section 1.1 includes five engaging lesson
activities.
18
6/13/14
Problems 1-9 through 1-12 part (a)
27
6/13/14
Then have teams begin their work without pointing
out the “Further Guidance,” which begins with
problem 1-20.
53
7/8/14
a.
107
6/13/14
regular pentagon
Chapter 1 Overview
Updated Section 1.1
sentence.
Lesson 1.1.2 Core
Problems
Corrected Version
1-12, not 1-11
Lesson 1.1.3 Suggested
Lesson Activity
Typo.
1-47. (a)
Extra square in diagram.
Lesson 1.3.1 Suggested
Lesson Activity.
regular hexagon
Change equilateral
pentagon and hexagon to
regular.
1-111. answers
111
6/13/14
Updated answer.
1-111. (c)
equilateral hexagon → regular hexagon
pentagon → regular pentagon
111
4/17/14
A kite has reflection symmetry.
119
6/13/14
a. Label each shape that you have learned about
so far with its geometric name.
Kite incorrect in answer.
1-120. (a)
Deleted.
The shapes on the resource page already have
names.
Errata for Core Connections Geometry
Page 1 of 37
Problem Number and
Description of Change
Page
Number
Date
120
6/13/14
Where would the regular hexagon from your
Shape Bucket go in this Venn diagram? What
about the trapezoid? Justify your reasoning.
[ regular hexagon: in only the right circle;
trapezoid: neither circle (Note: The trapezoid
in the Shape Bucket is not isosceles.) ]
120
5/2/14
b.
1-121. (b)
regular hexagon
1-123. (b)
Corrected Version
B
Diagram missing vertex
labels.
A
CL 1-134. (b)
C
132
7/22/14
b. y = 46 and y = –20
148
6/13/14
Avaiable for download at www.cpm.org.
173
3/13/14
“That means that it must have two pairs of angles
with equal measure.”
192
3/13/14
Yes, the angles marked by a and b form a straight
angle, so their measures sum to 180°.
194
3/13/14
Be sure to specify any relationship between the
measures of the angles (such as whether or not
they are always congruent).
210
3/13/14
Since the angles in ΔAEC must add up to 180°,
m∠BED must equal 0°.
Typo in answer.
Lesson 1.3.2B Resource
Page
Updated last row.
2-11.
Typo in sentence.
2-27. (c)
Typo in answer.
2-30.
Plural angles needed.
2-47. (b)
Incorrect triangle
referenced in answer.
Errata for Core Connections Geometry
Page 2 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
Lesson 3.2.1
Mathematical Background
335-336
7/7/14
However, a proof of AA~ is fairly straightforward.
Suppose we have ΔPQR and ΔTUV with
∠P = ∠T , and ∠Q = ∠U . Use rigid motions to
get
P′ =
T
 and the rays
ΔP′Q′R′ where
P′Q′ = TU and P′R′ = TV . Since rigid motions

preserve
angles,
we
can
think
of
the
lines
Q
′R′

and UV as lines with the same corresponding

angles when crossed by the transversal TU . So by
the converse of the corresponding
angle
 theorem

we know that the lines Q′R′ and UV are parallel.
Updated several typos.
U
R
At this point we may dilate ΔP′Q′R′ from P′ to
= U. Then since dilations
ΔP′′Q′′R′′ so that Q″


preserve parallels, Q′′R′′ is parallel
to UV and

both
contain U. Therefore Q′′R
lines

 ′′ is identical
UV
TV
to 
. Since
this line intersects
(which is

also P′′R′′ ) at V and R″, we must have V = R″.
Hence we have found a similarity transformation
taking ΔPQR to ΔTUV and so, by definition, the
two figures are similar.
U
Q
V
P
T
⇒
Q′
V
P′ = T
R′
We can also prove SAS~ in essentially the same
way but with even less work. Here we begin with
TV .
ΔPQR and ΔTUV with ∠P = ∠T , and TU
PQ = PR
As above, we use a
rigid
to
get ΔP
′Q′R′
 motion

where P′ = T and P′Q′ = TU and P′R′ = TV .
Since rigid motions preserve lengths, we also have
P′Q′ = PQ and P′R′ = PR . Dilate ΔP′Q′R′ from
P′ (= T) with scale factor PTU
to take Q′ to
= PTV
′Q′
′R′
U and R′ to V since dilations preserve ratios of
distances. This combination of a rigid motion and
a dilation is a similarity transformation that takes
ΔPQR to ΔTUV , so the two triangles are similar
by definition.
Errata for Core Connections Geometry
Page 3 of 37
Problem Number and
Description of Change
Page
Number
Date
244
10/6/16
3-58. (b)
Renamed second polygon
as to not use same letters
as first polygon.
Corrected Version
RIGHT ∼ ?
b.
I
R
G
F
A
T
Lesson 3.2.2 Math Notes
box.
S
L
349
1/19/16
352
12/31/14 b: Not enough information to determine similarity.
352
12/31/14 d: Rotation, reflection, and reduced by zoom factor
of 0.5 (or translation and reflection instead of
rotation and reflection).
356
3/13/14
For the diagrams in problem 3-71, find the lengths
of the segments listed below, if possible.
356
3/13/14
Yes, ΔPDQ ~ ΔYZX by SAS ~.
362
1/7/14
Problems 3-82, 3-83, 3-84, and 3-86
Corrected the definition of
congruent.
3-69. (b)
H
E
If there is a series of rigid transformations that
maps one shape onto the other, then the two
shapes are congruent.
Incorrect answer.
3-69. (d)
Typos in answer.
3-72.
Segments, not sides.
3-73. answer
Typo in triangle name.
Lesson 3.2.4 Core
Problems
Missing problem 3-84.
3-80.
361
Deleted first sentence as it
was not a mathematically
correct statement.
Lesson 3.2.4 Teacher
Notes
362-363
11/30/14 Each pair of figures below is related by a single
dilation. Solve for the indicated side lengths.
Show all work.
7/7/14
Changed “Robel” to “Cori” in three places.
Problem 3-86 is about
Cori, not Robel.
Errata for Core Connections Geometry
Page 4 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
362
7/7/14
If you do not have access to technology, testing
the proposed “SSA” similarity condition in
problem 3-86 is a bit tricky using straws or
linguini. One strategy is to tape a 5 cm straw
horizontally on a piece of paper. Using a
protractor, students can draw a ray from one
endpoint on their paper so that the angle at that
vertex is 49º. Students can then take a 4 cm straw
and place one of its endpoints on the opposite end
of the 5 cm straw of the new triangle. They can
move it around on the paper, trying to place the
other endpoint on the ray they have drawn. They
should find that two possible triangles can be
produced, one of which is not similar to Cori’s.
372
3/13/14
You now have a complete list of the three triangle
similarity conditions (AA ~, SAS ~, and SSS ~)
that can be used to verify that two triangles are
similar.
388
12/31/14 Since the diagram does not show that lines m and
n are parallel, it cannot be concluded that
∠a ≅ ∠b. Students can use a diagram where lines
n and m do not look parallel to show that angles a
and b are not congruent.
399
1/17/14
Updated resource page available for download at
www.cpm.org.
425
2/8/15
Since the slope ratio is ≈
437
3/13/14
Encourage students to either trace the triangle to
orient it as a slope triangle or to discuss how they
can visualize transforming it to identify Δy and Δx.
438
7/7/14
The prompt in problem 4-38 asks students to write
a Learning Log entry about how to find Δy and Δx.
In order to be sure that students have accurate
explanations, it is recommended that you pull the
class together in the last 2 or 3 minutes and write a
class reflection with a diagram, such as one of the
triangles provided in problem 4-37.
Lesson 3.2.4 Technology
Notes
Deleted references to
points that did not exist
and corrected incorrect
lengths.
Lesson 3.2.5 intro
Triangle singular, not
plural.
Chapter 3 Portfolio (c)
Typos in answer.
Lesson 3.2.1 Resource
Page
Updated so point of
dilation could be found.
4-12.
1
5
, y ≈ 4.
Typo in answer.
Lesson 4.1.4 Suggested
Lesson Activity
5th paragraph, it not is.
Lesson 4.1.4 Closure
Updated paragraph.
Errata for Core Connections Geometry
Page 5 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
441
1/6/14
In part (a), you calculated the slope ratio for 32° as
0.625. Use the “tan” button on your calculator to
verify that you get approximately 0.625 when you
enter 32°. Does that button give you
approximately 1.600 when you enter 58°?
443
11/14/16
4-36. (c)
≈ changed to
approximately.
4-40. (c)
146.8°
Impossible triangle.
5
12
20°
146.8°
3
20°
x
4-51. (b)
an = −7.5 − 2(n − 1) = −5.5 − 2n
450
11/9/14
455
11/30/14 b:
Typo in answer (–5.5 not
5.5).
4-54. (b) and (c)
Answers are exact, not
approximate.
4-58. (c)
c:
459
5/2/14
Typo in first sentence.
4-66. (c)
=
21
40
= 52.5%
Is the probability that the second contestant is a
girl independent of the first contestant being a
girl?
475
11/30/14 1 point is represented by the upper right portion of
the model.
483
9/8/14
484
1/7/14
495
1/7/15
Updated wording to be
mathematically and
grammatically correct.
4-90.
7
3
10 · 4
11/30/14 After 100 attempts, and Romeo finds has found
the cheese 66 times.
Incorrect location stated.
4-89. (a)
= 17.5%
465
Updated wording in first
sentence.
4-78. (c) answer
7
40
Calculate the probability of winning either the bet
on the event {7, 8, 10, 11} or the bet on the event
{10, 11, 12, 13, 14, 15}. Think about the set of
outcomes that will allow the bettor to win either of
the bets. This set of outcomes is the union of the
two events.
4
38
6 − 2 =
+ 38
38
8
38
Typo in fraction equation.
4-105. (c)
2(0.36) + 1(0.24) + 0(0.4) = 0.96
Typo in answer.
Errata for Core Connections Geometry
Page 6 of 37
Problem Number and
Description of Change
Page
Number
Date
496
4/6/14
4-106. (a) and (c)
Updated answers.
CL 4-123. (b) answer
Corrected Version
a: The expected value should be 0.
c: Answers vary, but the sum of the faces must be
0. For example, change either a –4 to a –3, or
change a 2 to a 3.
509
7/7/14
Incorrect first bubble in
flowchart.
m∠CDB = m∠CEA
m∠BCD = m∠ACE
ΔBCD ~ ΔACE
5-8. (c)
542
3/13/14
False (it does not mention that the lines must be
parallel)
548
4/28/15
Since the spins are independent, …
561
1/21/14
Write an equation for each sequence.
569
3/20/14
Decide if each pair of triangles below are similar.
If they are similar, give a sequence of
transformations that justifies your conclusion. If
they are not similar, explain how you know.
Answer had incorrect
punctuation.
5-20.
Typo in answer.
5-43.
Updated problem prompt.
5-58.
Removed “rigid” from
problem prompt and
updated answers.
a: Not similar
b: Similar: Rotate ΔGHI, translate, then dilate.
c: Similar: Reflect ΔMNP, translate, then dilate.
d: Similar: Rotate ΔTUV, translate, then dilate.
5-65. (b)
575
2/23/15
Answers vary. Once students solve for all the
angles, they need to state that two pairs of
corresponding angles have equal measure, such as
m∠A = m∠D and m∠B = m∠E to reach the
conclusion that ΔABC ~ ΔDEC by AA ~ or AC =
AC
BC and DC = EC, so DC
= BC
EC and
m∠ACB = m∠DCE therefore
ΔABC ~ ΔDEC SAS ~.
576
9/8/14
cos 38º = sin 52º
Updated answer.
5-66.
Typo in last answer.
Errata for Core Connections Geometry
Page 7 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
591
1/21/14
Stephen does not like yogurt very much, but he
loves apples. Since both make a good snack,
Stephen’s mom makes a deal with Stephen. She
will keep the refrigerator stocked with 5 yogurts, 2
green apples, and 3 red apples every day. Each
day, Stephen will randomly pick a snack. What is
the probability Stephen will not get three yogurts
on three consecutive days? Use a tree diagram or
area model to show all the possible outcomes in
the sample space.
600
1/21/14
Note that there is not a way to solve for the second
solution other than to subtract the first solution
from 180º. Students will learn in a subsequent
course that sin x = # generally has two solutions
for 0º ≤ x ≤ 360º by using a unit circle, but a
calculator will only provide one solution.
609
1/7/15
Does this confirm the results from problem 5-118?
618
2/8/15
5-93.
Switched order of last two
sentences.
Lesson 5.3.4
Added to first paragraph
of the Suggested Lesson
Activity.
5-119.
Incorrect problem
reference in last sentence.
Chapter 5 Portfolio
Part (b) number (1)
triangle missing leg
length.
Chapter 5 Portfolio
x
60°
5
619
2/8/15
The color of the bike is independent of its type.
620
7/7/14
If m∠B = 80º, m∠ACB = 29º, AB = 14, and
DE = 12, find CE.
624
12/8/14
Part (b) number (3) added
sentence for clarity.
CL 5-140. (b)
29 degree angle was
missing its degree symbol.
CL 5-140. (a) answer
Similar, not congruent in
last bubble.
∠ACB ≅ ∠ECD
∠B ≅ ∠D
ΔACB ~ ΔECD
AA ~
CL 5-140. (b) answer
624
7/7/14
b. CE ≈ 24.38
“x” is not in the problem.
CE, not x.
Errata for Core Connections Geometry
Page 8 of 37
Problem Number and
Description of Change
Page
Number
Lesson 5.3.1 Resource
Page
Date
Corrected Version
629
10/28/14 Updated resource page available for download at
www.cpm.org.
645
1/19/16
If two figures have the same shape and are the
same size, they are congruent. Since the figures
must have the same shape, they must be similar.
657
4/6/14
Then Mary Sue added, “Oh, then we can rotate
ΔA′B′C′ about point D to get ΔA″B″C″ with


A′′B′′ pointing in the same direction as DE , ...
658
2/8/15
Discuss how their previous strategy needs to be
changed to show that these triangles are congruent
using rigid transformations.
665
1/6/14
m∠PRQ = m∠TRS
670
3/13/14
Problem 6-45 asks students to complete a Learning
Log entry about converses.
671
3/13/14
Do you think that all converses of true statements
are also true?
678
1/7/15
Shortened edge length arrows to indicate length of
table on the inside.
679
1/7/15
Removed diamonds from edges of table.
Diagram (a) was missing
side labels.
Lesson 6.1.1 Math Notes
box
Deleted incorrect
definition of congruent.
6-20.
4th paragraph: with not
with the
6-20. (b)
Rigid transformations, not
translations.
6-31. answer
Typo in angle name.
Lesson 6.1.5 Closure
Incorrect problem
reference.
6-42.
Updated question in
problem prompt.
6-53.
Updated diagram.
6-54. (b)
Updated diagram.
6-55. (c)
Also updated the resource page.
680
2/8/14
x ≈ 265.48
686
3/26/14
No special statements can be made because
vertical angles are always equal.
Incorrect answer.
6-62. (c)
Typo in answer. Angles,
not lines.
Errata for Core Connections Geometry
Page 9 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
692
1/7/15
The ball must be hit from at least ≈ 8.57 ft.
Depending on where Carina stands, the ball may
hit the ground at an angle of ≈ 7.5º to 8.1° with the
ground.
693
12/8/14
What triangle tool can you use to find the angle of
depression of the path of the ball? Find the acute
angle the path of the ball makes with the ground.
[ inverse tangent; ≈ 8.13° ]
702
3/26/14
If the base angles of a triangle are congruent, then
it is isosceles.
710
3/26/14
x ≈ 49.94 , Triangle Angle Sum and isosceles
triangle
772
2/23/15
Also, congruent triangles guarantee that
m∠ADC = m∠BDC. Since
m∠ADC + m∠BDC = 180º, then m∠ADC = 90º
and the diagonals must be perpendicular.
774
6/20/14
Write an equation for each of the following
sequences.
775
12/8/14
Similar, because if the Pythagorean Theorem is
used to solve for each unknown side, then 3 pairs
of corresponding sides have a common ratio; thus,
the triangles are similar by SSS ~).
781
3/26/14
6-68. (a)
Incorrect angle answer.
6-70. (c)
Deleted reference to angle
of depression.
Incorrect answer.
6-86. (a)
Typo in problem. Then,
not the.
6-97. (d)
Degrees symbol deleted
from answer.
7-52. (d)
Typo in answer.
7-57.
Updated wording
(equation not expression).
7-59. (c)
Incorrect answer.
7-63.
T
U
b
“c” missing from diagram.
W
Lesson 7.2.3 Suggested
Lesson Activity
786
3/26/14
a
V
As students offer statements of fact, create a list for
whole-class display with each fact and reason.
Last full paragraph,
display, not diplay.
Errata for Core Connections Geometry
Page 10 of 37
Problem Number and
Description of Change
Page
Number
Date
802
1/22/14
m∠PMA = m∠PMB = 90º
810
3/26/14
∠JEF ≅ ∠H and ∠G ≅ ∠JFE (if lines are
parallel, corresponding angles are congruent).
Therefore, ∠JEF ≅ ∠JFE.
827
1/7/15
Graph on ABCD if A(1, 4), B(6, 6), C(4, 1), and
D(–1, –1).
834
5/2/14
Thus, if A(1, 3) and B(5, 8) , then Δx = 5 − 1 = 4
and Δy = 8 − 3 = 5 . Then the x-coordinate of M is
1+ 12 (4) = 3 and the y-coordinate is
3 + 12 (5) = 5.5 . So point M is at (3, 5.5).
848
2/1/14
Must be: none; Could be: rectangle, square,
isosceles trapezoid
878
3/26/14
Later, after students use this method repeatedly in
problem 8-14, students should notice that the
number of triangles is always two less than the
number of sides of the polygon.
878
3/20/14
Discuss problem 8-14 before moving teams on to
problems 8-15 and 8-16.
881
3/26/14
Rhombus: Since a rhombus is a parallelogram, it
has all of the properties of a parallelogram. In
addition, its diagonals are perpendicular
bisectors that bisect the angles of the rhombus;
the diagonals also create four congruent
triangles.
883
2/8/15
All of these are correct
7-92.
Corrected Version
Typo in “Statements”
column of proof.
7-106. (c)
Updated answer as angles
E and F were ambiguous.
7-131. (a)
Deleted the word “on”.
Lesson 7.3.3 Math Notes
box
Incorrect midpoint given
in example.
CL 7-156. (a)
Incorrect answer.
Lesson 8.1.2 Suggested
Lesson Activity
Incorrect problem
reference 4th paragraph.
Lesson 8.1.2 Suggested
Lesson Activity
Incorrect problem
reference in last
paragraph.
Lesson 8.1.2 Math Notes
box
Updated wording in
“rhombus” paragraph.
8-23. (e)
Incorrect phrase.
Errata for Core Connections Geometry
Page 11 of 37
Problem Number and
Description of Change
Page
Number
Date
884
3/20/14
They will also construct viable arguments for
problems that result in no solution and write
counterexamples.
906
3/21/14
A quadrilateral with diagonals that are
perpendicular bisectors of each other.
[ Rhombus ]
911
2/7/14
Write down any observations or patterns you
found while working on problem 8-67.
919
2/23/15
His girlfriend decides to divide the cookie into 12
separate but congruent pieces. After 9 of the
pieces have been eaten, what area of the cookie is
left?
919
4/1/16
a150 = – 57.5
920
2/8/15
∠ADB ≅ ∠CBD
921
5/2/14
Students will discover the area and circumference
formulas for a circle with radius 1.
Lesson 8.1.3
Mathematical Practices
Sentence ended in a
comma.
8-61. (d)
Updated wording and
answer.
8-68.
Incorrect problem
reference.
8-84. (b)
Updated wording.
8-86.
Corrected Version
Incorrect answer.
8-87.
Typo in middle bubble of
flowchart.
Lesson 8.3.1
Lesson Objective updated.
Lesson 8.3.1
922
11/30/14 Take this opportunity to congratulate the class for
discovering π. You may want to elaborate that
making predictions based on data like this is one
of the core concepts of calculus. Then problem
8-92 asks students to write a Learning Log entry
about what they learned during this lesson. You
could have the students do a Peer Edit.
926
2/23/15
6x + 18º = 2x + 30º, x = 3°
933
2/23/15
P ≈ 10.2 units
Closure updated.
8-97. (b)
Typo in answer.
8-106. (b)
Incorrect answer for
perimeter.
Errata for Core Connections Geometry
Page 12 of 37
Problem Number and
Description of Change
Page
Number
Date
934
9/8/14
If the length of a side of the polygon is 2 units,
what is the area of the polygon?
935
7/7/14
Box with string or one string per team to simulate
problem 8-114, recommended
938
5/2/14
In Lesson 8.3.2, you developed methods to find
the area and circumference of a circle with
radius r.
941
3/20/14
AC = BC
942
6/20/14
2.8 and –2.8
943
4/29/15
a: supplementary angles sum to 180º; x = 26º
8-107. (b)
Missing the word units.
Lesson 8.3.3 Materials
Incorrect problem
reference.
Lesson 8.3.3 introduction
Incorrect lesson reference.
8-118.
Corrected Version
Statement 4 does not need
segment bars.
8-120. (c)
Incorrect answer.
8-124.
Typo in answer (c) and all
answers missing degree
symbols.
8-125. (b)
b: alternate exterior angles are congruent; x = 5º
c: Triangle Angle Sum Theorem; x = 15º
d: exterior angle equals sum of remote interior
angles; x = 35º
944
2/27/15
If the area of ΔABE is 19 cm2, what is the area of
ΔACD? [ 19(4) = 76 cm2 ]
944
2/23/15
square cm in both answers
952
2/8/15
m∠C = 32º
950
4/28/15
Updated problem to
correct area of triangle.
8-128.
Answers need “cm” not
units.
CL 8-133. (d)
Typo in answer.
CL 8-136. (a)
Impossible quadrilateral in
diagram.
2x + 50º
3x + 25º
x = 25º
Errata for Core Connections Geometry
Page 13 of 37
Problem Number and
Description of Change
Page
Number
8-138. (e)
950
Date
10/28/15 e.
Updated wording.
CL 8-139. (b)
Corrected Version
Find the measure of an exterior angle of a
regular polygon with 10 sides.
953
2/8/15
m = 50º, supplementary angles
i = 51º, Triangle Angle Sum Theorem
982
12/9/14
986.16 · 16 ≈ 15,778.61 square mm
1010
4/6/14
uuur
That is, find AD such that ∠BAD ≅ ∠CAD.
Updated answer.
9-20. (b)
Typo in answer.
9-64. (d)
Typo in last sentence.
∠CAD not ΔCAD.
New diagram in which AB = AC.
Updated diagram.
9-73.
1015
4/29/15
Bread
Incorrect tree diagram
answer.
Protein
Condiment
mayo
salami
white
plain
mayo
turkey
plain
mayo
ham
plain
mayo
salami
grain
plain
mayo
turkey
plain
mayo
ham
9-101. (d)
plain
1038
9/8/14
How does this help explain that
1054
4/1/14
Updated resource page available for download at
www.cpm.org.
BP
BE
=
2
3
?
Last fraction had an
incorrect denominator.
Lesson 9.2.1 Resource
Page
First row of page 2 is
problem 9-65 (d).
Errata for Core Connections Geometry
Page 14 of 37
Problem Number and
Description of Change
Ch. 10 Suggested
Assessment
Page
Number
Date
1073
7/8/14
Counting the number of outcomes in complex
cases that require combining smaller counts of
permutations and/or combinations, as in problem
10-179 and in the classwork problems of Lesson
10.3.5.
1086
7/8/14
x = 56º, y = 28º
1094
12/8/14
a. Timothy decided to create two triangles
(ΔBED and ΔAEC).
Typo in 2nd to last bullet.
Combining, not combing.
10-16. (f) answer
Corrected Version
Both answers were x = .
10-27.
Incorrect triangle names.
AEC not ACE.
10-28.
c. How are ΔBED and ΔAEC related?
1094
4/17/14
A polygon is said to be inscribed in a circle when
each of its vertices touch the circle.
1096
4/29/15
 = 2 p − 2k = 2( p − k) = 2m∠EAC
mEC
1097
7/8/14
 and
a. What is the relationship between AB
 ? How do you know?
CD
Typo: its, not is.
Lesson 10.1.3 Math Notes
box
Incorrect formula in
second to last paragraph.
10-32.
Updated wording in parts
(a) and (b).
Lesson 10.1.4 Suggested
Lesson Activity
 or CD
?
b. Which has greater measure AB
Which has greater length? Explain.
1099
7/8/14
If time allows, problem 10-42 prompts students to
prove that the intersection of the angle bisectors of
a triangle is the center of a circle that is inscribed
in the triangle (a relationship introduced in
Chapter 9).
1103
7/8/14
Using the same reasoning as in part (b),
ΔBPD ≅ ΔBFP because of AAS since ray BP is
an angle bisector.
1112
4/29/15
In part (d) of this problem, students are introduced
to the term mutually exclusive events.
Incorrect problem
reference in last
paragraph.
10-42. (d) answer
Incorrect triangles listed.
Lesson 10.2.1 Suggested
Lesson Activity about
10-62
Incorrect statement in
sentence.
Errata for Core Connections Geometry
Page 15 of 37
Problem Number and
Description of Change
Lesson 10.2.1 Closure
notes
Page
Number
Date
1113
4/29/15
Mutually exclusive means that both events cannot
occur together or at the same time (like {live on
campus} and {engineering} in problem 10-64),
while independent means that knowing that one
event has occurred does not change the
probability of the other event (like {female} and
{jeans} in problem 10-63).
1127
12/8/14
Shade the cells in your table from part (b) where a
student has previously taken the folder.
1130
1/7/14
m∠C = 0.5(194º) = 97º
1139
4/17/14
Thus, the heights for 175 people randomly
selected people are independent of their IQs.
1140
2/8/15
•
1142
1/22/16
1142
4/11/16
Charlie’s neighbor subscribes to at least one
paper.
1143
11/2/15
The Sunshine Orange Juice Company wants its
product in a one-quart container (1 quart equals
57.75 cubic inches). The manufacturer for their
containers makes cylindrical cans that have a base
that is 5 inches in diameter. What will be the
height of the one-quart container?
Incorrect sentence in
fourth paragraph.
10-76. (d)
Incorrect part reference.
10-87. (b)
Corrected Version
Typo in answer – 194, not
1.94.
10-97.
Repeated word.
10-100.
State the Addition Rule.
First bullet should be
singular.
10-102.
Updated art.
10-102. (c)
Updated wording to be
clearer.
10-103.
Incorrect conversion
given. Problem and
answer updated.
57.75 ≈ 2.94
[ 57.75 = π(2.52)h, h = 6.25
in. ]
π
Errata for Core Connections Geometry
Page 16 of 37
Problem Number and
Description of Change
10-122. (d)
Page
Number
Date
1156
4/29/15
How many three-number locker combinations
could Carmen make up if zero could only be the
second or third number and none of the numbers
can be repeated?
1157
4/17/14
How is this list different from all the arrangements
a child can make on a line on the refrigerator door
with three magnetic letters A, B, and C?
1159
3/27/14
a: 7! = 5040
Three-number, not threedigit.
10-123. (a)
First sentence below box
is a question.
10-127.
Typos in answers.
10-130.
Corrected Version
b:
1160
1/10/14
Typos in answer fractions
and two-way table added.
1
5040
See two-way table at right. No, they should not
charge a higher premium.
9 = 0.02586
P(ticket given red) = 348
507 = 0.02535
and P(ticket) = 20,000
.
red car
not red car
ticket
9
no ticket
348
507
10-131.
20000
1161
1/21/14
0.64 ⋅ 0.28 ≠ 0.22
1162
4/17/14
For example, in order to calculate
the home screen and enter 20.
1162
7/8/14
Prepare in advance by verifying that you know
how to find permutations and combinations on the
calculator models your students use.
1165
2/8/15
The number of permutations is 6 times greater
than the number of combinations for the 5 choose
3 situation and 24 times greater for the 6 choose 4
situation.
1167
2/8/15
For the each of the following expressions, write
down a factorial expression and then compute the
value.
Typo in answer. 0.64 not
0.68.
Lesson 10.3.3 Materials
Updated last paragraph
(added 20 C 4).
Lesson 10.3.3 Suggested
Lesson Activity
Students plural.
10-135. (a)
Typos in answer.
10-141.
Typos in first sentence.
Errata for Core Connections Geometry
20
C4 , start from
Page 17 of 37
Problem Number and
Description of Change
10-141. (b)
Page
Number
Date
1167
2/8/15
Typo in answer.
10-142.
10 P 8, not 10 P 2
10 C8
=
10 P8
8!
=
10!
8!2!
= 45
1168
9/8/14
Avoid the common mistake of computing
P(no caffeine and no dairy) = 1 –
P(coffee and dairy) because {coffee and dairy}
includes all the drinks that have both coffee and
dairy but does not include drinks that have only
coffee or only dairy.
1175
1/21/14
Charlie and his nephew, Jake, who is a bottomless
hunger pit, went to the state fair. Charlie had
promised he would buy Jake three snacks. He
can have one when they arrive, one midafternoon, and one when they were about to
leave, or, as Jake prefers, he can have all of the
snacks all at once. At the food stand the menu
included seven items:
Incorrect statement in last
sentence of answer.
10-150.
Corrected Version
Updated wording.
…
Jake likes everything on the menu so much that
he would not mind having any three items or
even any two or three of the same thing. Uncle
Charlie thinks variety is good so he wants Jake to
choose three different things.
10-151.
1175
1/21/14
Charlie gets his way 13 of the time, so the
probability that he gets his way for both “order”
and “repetition” is 13 ⋅ 13 = 19 .
1188
9/8/14
13 ( 4 C3 ) ( 12 C2 ) (4)(4) = 54912
1188
2/8/15
Use a similar method for calculating the
probability of getting two of a kind.
1188
2/8/15
What is the probability of getting two pairs?
1188
4/29/15
Updated answer wording.
10-172. (d)
Answer should be a whole
number, not a probability.
10-172. (f)
Two of a kind, not one
pair and then another pair.
10-172. (g)
Added question.
10-172. (g)
Typos in answer.
Errata for Core Connections Geometry
13 C2 ⋅4 C2 ⋅4 C2 ⋅11⋅4
52 C5
= 123,552
C ≈ 0.0475
52 5
Page 18 of 37
Problem Number and
Description of Change
Lesson 10.3.5 Resource
Page
Page
Number
Date
Corrected Version
2/8/15
Incorrect answers.
1205
and
1206
11-48.
1245
4/17/14
1248
12/31/14 Students should connect both their work with
regular polygons and circles and their work with
pyramids and prisms to reason out the relationship
between the volume of pyramids and cones.
Updated “royal flush” and “bust” answers.
Updated resource page available for download at
www.cpm.org.
(ASA ≅)
Typo in answer. ASA not
AAS.
Lesson 11.1.4 Suggested
Lesson Activity
Typo in last sentence of
third paragraph.
11-99.
1278
9/8/14
Find the area of a regular decagon if the length of
each side is 20 units.
[ Central angle = 36°, distance from center to
midpoint of side = 30.777 units,
A = 12 (20)(30.777)(10) ≈ 3077.7 square units ]
1289
7/8/14
Assume that the radius of the Earth is 4000 miles.
1300
5/27/15
Number with primarily birds and under $20,000
should be 9 (not 69).
1301
9/8/14
She plans to tie three loops of ribbon about the
package as shown at right.
1303
5/27/15
e: Either sum the appropriate cells:
Updated problem wording
and answer.
11-114. (a)
Missing the word “is”.
CL 11-129.
Updated data to sum to
1000.
CL 11-131. (b)
Three, not two.
CL 11-129. (e) and (f)
64+63+9+3+70+66+59+7+3+41+77+82+97
1000
Incorrect answers.
= 64.1%
or use the Addition Rule:
385
386
130
641
1000 + 1000 − 1000 = 1000 = 64.1%
f: P(dog given < $35,000) =
64+66
64+63+9+3+70+66+59+7+3+41 = 33.7%
CL 11-130. (a)
1303
4/3/14
ΔABC ~ ΔRTS (AA~)
Missing parenthesis in
answer.
Errata for Core Connections Geometry
Page 19 of 37
Problem Number and
Description of Change
Lesson 12.1.1 Suggested
Lesson Activity
Page
Number
Date
1328
7/8/14
Problem 12-4 gives students the opportunity for
more practice in a slightly different context.
1330
7/8/14
Add a point P to your diagram and then draw a
right triangle like ΔABP in the circle at right.
1336
4/3/14
In problem 12-36, teams should find a total of
seven cross-sections. When they call the
hyperbola a “double parabola,” correct them
(hyperbolas are not made from two parabolas),
and again, indicate that they will be studied in a
later course.
1350
4/17/14
The farther the focus is to the directrix, the wider
the parabola is and vice versa.
1353
4/3/14
Emphasize that since the distances from the points
on the parabola to the directrix and to the focus are
equal, then the the expressions for each of these
distances can be set equal to each other.
1372
7/8/14
y-intercept: (0, 6)
1360
4/28/15
b:
1365
4/28/15
The base angles of ΔPSR must add up to 40° so
that the sum of all three angles is 180°. Then add
the 40° and 35° of ∠QPS and ∠QRS, respectively,
and the sum of the base angles of ΔPQR must be
115°.
Corrected Version
Incorrect problem
reference in last
paragraph.
12-3. (a)
Incorrect triangle
referenced.
Lesson 12.1.3 Suggested
Lesson Activity
Typo in paragraph for
problem 12-36.
12-38. (c)
Typo in answer.
Lesson 12.1.4 Suggested
Lesson Activity
3rd paragraph, last
sentence, deleted the extra
“the”.
12-73. (a)
Incorrect y-intercept.
12-55. (b)
Typo in answer.
12-61.
Typos in answer.
Errata for Core Connections Geometry
5 C2 ⋅4 C1
12 C3
=
40
220
≈ 18.2%
Page 20 of 37
Problem Number and
Description of Change
12-66.
Page
Number
Date
1366
4/28/15
Corrected Version
8
6
Incorrect answer.
4
2
-10
-5
5
10
-2
-4
-6
-8
12-82. (c)
1381
7/8/14
Several typos in answer.
Hint: Students can start by determining the interior
angles of the pentagon inside the star. The
pentagon has interior angles of 108°, therefore
m∠B = 108°. By drawing the bisector of ∠B,
72°
AB = sin0.554° . BD = cos
sin 54° . It follows that
AB
BD
AB
BD
12-85.
=
=
72°
0.5
+ cos
sin 54° + sin 54° ≈ 1.6180 = φ and
0.5
cos 72°
sin 54° + sin 54°
0.5
sin 54°
0.5
sin 54°
cos 72°
sin 54°
≈ 1.6180 = φ .
1383
2/23/15
Thus, the y-coordinate of point C could be
2 ± 2 3 ; (5, ≈ 5.46) or (5, ≈ −1.46) .
11
4/28/15
Example 2:
Calculate the area and perimeter.
Typo in answer. 5.46 not
7.46.
Checkpoint 4
Impossible triangle in
Example 2.
9.85 cm
4 cm
5 cm
6 cm
A = 12 bh = 12 ⋅ 6 ⋅ 4 = 12 cm 2
P = 6 + 5 + 9.85 = 20.85 cm
Checkpoint 4
13, 14
6/1/16
10 ft
10 ft
Impossible diagram in
problem #7.
16 ft
8 ft
12 ft
7.
Errata for Core Connections Geometry
A = 144 ft2, P = 64 ft
Page 21 of 37
Problem Number and
Description of Change
Page
Number
Date
27
4/28/15
Checkpoint 7
Corrected Version
4.
Diagrams in problems 4
and 5 were missing the
parallel marks.
15
z
4
45°
22
7
5.
y
10
6
17
Checkpoint 8
31
4/29/15
a: supplementary angles sum to 180º; x = 26º
b: alternate exterior angles are congruent; x = 5º
c: Triangle Angle Sum Theorem; x = 15º
d: exterior angle equals sum of remote interior
angles; x = 35º
Checkpoint 8
32
Diagrams in first three
practice problems
repeated CL 8-137 and
had incorrect answers.
4/29/15
1.
2.
4x – 2º
3x + 2º
3.
y – 48º
3y
101º
34º
z
Checkpoint 8
32
All work was missing degree symbols.
Ex: (b) 5x + 6º = 2x + 21º
3x = 15º
x = 5º
Now we can go back and
solve the original
problems work updated.
Checkpoint 8
4/29/15
32
12/21/15 10.
m + 8º
Impossible triangle in
problem #10.
2m – 3º
Errata for Core Connections Geometry
m + 6º
Page 22 of 37
Problem Number and
Description of Change
Page
Number
Date
33
4/28/15
congruent vertical angles, supplementary sameside interior; x = 18.5º, y = 22.5º
34
4/29/15
See errata for problem 9-73.
35
9/8/14
Checkpoint 8
All practice problem
answers need the degree
symbol. Answer 18 was
incorrect.
Checkpoint 9A
Corrected Version
Incorrect tree diagram
answer.
Checkpoint 9A
Example 1
First Drink
Incorrect entries in table.
hot coffee
Second
Drink
Checkpoint 9A
problem 1 (b) answer
hot tea
hot
coffee
hot
tea
5
8
2
8
25
64
10
64
10
64
5
8
2
8
frozen coffee
slush 18
frozen
coffee
slush
5
8
5
64
5
64
42
9/8/14
0.09 = 9%
51
9/8/14
≈ 172.0 ft2
55
5/27/15
V ≈ 2.362 m 3; SA ≈ 10.85 m 2
5
4/29/15
Cavalieri’s Principle Two solids have the same
volume if corresponding cross-sectional areas are
the same. For example, an oblique solid has the
same volume as the corresponding right solid with
the same height, as long as all the cross-sections
parallel to the base have the same area.
Incorrect answer.
Checkpoint 10
problem 11 answer
Incorrect answer.
Checkpoint 11
problem 7 answers
Incorrect answers.
Glossary – Cavalieri’s
Principle
Parallel, not
perpendicular.
Errata for Core Connections Geometry
Page 23 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
7
1/19/16
congruent Two shapes are congruent if there is a
sequence of rigid transformations that carries one
onto the other. The corresponding angles and
sides of congruent polygons have equal measures.
Congruent shapes are similar and have a scale
factor of 1. The symbol for congruence is ≅.
27
1/19/16
similar figures Two shapes are similar if there is
a sequence of rigid motions, followed by a
dilation, that carries one onto the other. The
corresponding angles of similar polygons are
congruent, and the corresponding sides are
proportional. The symbol for similar is ~ . See
also ratio of similarity.
28
4/29/15
slope angle The acute angle a line forms with the
x-axis on a coordinate graph. Also see slope
triangle.
Glossary – congruent
New definition.
Glossary – similar figures
New definition.
Glossary – slope angle
New definition.
Errata for Core Connections Geometry
Page 24 of 37
Changes to the Student Version:
Problem Number and
Description of Change
1-47. (a)
Page
Number
Date
28
7/8/14
a.
67
6/13/14
a. Label each shape that you have learned about so
far with its geometric name.
Corrected Version
Extra square in diagram.
1-120. (a)
Deleted.
The shapes on the resource page already have
names.
1-121. (b)
68
6/13/14
Where would the regular hexagon from your Shape
Bucket go in this Venn diagram? What about the
trapezoid? Justify your reasoning.
68
5/2/14
b.
regular hexagon
1-123. (b)
B
Diagram missing vertex
labels.
C
A
CL 1-134. (b)
76
7/22/14
b. y = 46 and y = –20
84
3/13/14
“That means that it must have two pairs of angles
with equal measure.”
94
3/13/14
Be sure to specify any relationship between the
measures of the angles (such as whether or not they
are always congruent).
172
10/6/16
b.
Typo in answer.
2-11.
Typo in sentence.
2-30.
Plural angles needed.
3-58. (b)
Renamed second
polygon as to not use
same letters as first
polygon.
RIGHT ∼ ?
I
R
F
A
T
Errata for Core Connections Geometry
G
H
E
S
L
Page 25 of 37
Problem Number and
Description of Change
Lesson 3.2.2 Math
Notes box.
Page
Number
Date
Corrected Version
175
1/19/16
If there is a series of rigid transformations that maps
one shape onto the other, then the two shapes are
congruent.
178
3/13/14
For the diagrams in problem 3-71, find the lengths of
the segments listed below, if possible.
181
9/8/14
y = −2x + 7
Corrected the definition
of congruent.
3-72.
Segments, not sides.
3-77. (c)
Incorrect answer.
3-80.
182
11/30/14 Each pair of figures below is related by a single
dilation. Solve for the indicated side lengths. Show
all work.
189
3/13/14
You now have a complete list of the three triangle
similarity conditions (AA ~, SAS ~, and SSS ~) that
can be used to verify that two triangles are similar.
227
1/6/14
In part (a), you calculated the slope ratio for 32° as
0.625. Use the “tan” button on your calculator to
verify that you get approximately 0.625 when you
enter 32°. Does that button give you approximately
1.600 when you enter 58°?
229
11/14/16
Deleted first sentence as
it was not a
mathematically correct
statement.
Lesson 3.2.5 intro
Triangle singular, not
plural.
4-36. (c)
≈ changed to
approximately.
4-40. (c)
Impossible triangle.
146.8°
5
12
20°
146.8°
x
4-58. (c)
239
Typo in first sentence.
4-66. (c)
243
Updated wording in first
sentence.
Errata for Core Connections Geometry
5/2/14
3
20°
Is the probability that the second contestant is a girl
independent of the first contestant being a girl?
11/30/14 After 100 attempts, and Romeo finds has found the
cheese 66 times.
Page 26 of 37
Problem Number and
Description of Change
4-89. (a)
Page
Number
Date
Corrected Version
252
9/8/14
Calculate the probability of winning either the bet on
the event {7, 8, 10, 11} or the bet on the event {10,
11, 12, 13, 14, 15}. Think about the set of outcomes
that will allow the bettor to win either of the
bets. This set of outcomes is the union of the two
events.
253
1/7/14
272
7/7/14
Updated wording to be
mathematically and
grammatically correct.
4-90.
4
38
6 − 2 =
+ 38
38
8
38
Typo in fraction
equation.
CL 4-123. (b) answer
Incorrect first bubble in
flowchart.
m∠CDB = m∠CEA
m∠BCD = m∠ACE
ΔBCD ~ ΔACE
5-43.
295
1/21/14
Write an equation for each sequence.
301
3/20/14
Decide if each pair of triangles below are similar. If
they are similar, give a sequence of transformations
that justifies your conclusion. If they are not
similar, explain how you know.
315
1/21/14
Stephen does not like yogurt very much, but he loves
apples. Since both make a good snack, Stephen’s
mom makes a deal with Stephen. She will keep the
refrigerator stocked with 5 yogurts, 2 green apples,
and 3 red apples every day. Each day, Stephen will
randomly pick a snack. What is the probability
Stephen will not get three yogurts on three
consecutive days? Use a tree diagram or area model
to show all the possible outcomes in the sample
space.
325
1/7/15
Does this confirm the results from problem 5-118?
Updated problem
prompt.
5-58.
Removed “rigid” from
problem prompt.
5-93.
Switched order of last
two sentences.
5-119.
Incorrect problem
reference in last
sentence.
Errata for Core Connections Geometry
Page 27 of 37
Problem Number and
Description of Change
Chapter 5 Portfolio
Page
Number
Date
332
2/8/15
Part (b) number (1)
triangle missing leg
length.
Chapter 5 Portfolio
Corrected Version
x
60°
5
333
2/8/15
The color of the bike is independent of its type.
334
7/7/14
If m∠B = 80º, m∠ACB = 29º, AB = 14, and DE = 12,
find CE.
338
12/8/14
Part (b) number (3)
added sentence for
clarity.
CL 5-140. (b)
29 degree angle was
missing its degree
symbol.
CL 5-140. (a) answer
Similar, not congruent
in last bubble.
∠ACB ≅ ∠ECD
∠B ≅ ∠D
ΔACB ~ ΔECD
AA ~
CL 5-140. (b) answer
338
7/7/14
b. CE ≈ 24.38
345
1/19/16
If two figures have the same shape and are the same
size, they are congruent. Since the figures must have
the same shape, they must be similar.
353
2/8/15
Discuss how their previous strategy needs to be
changed to show that these triangles are congruent
using rigid transformations.
361
3/13/14
Do you think that all converses of true statements are
also true?
366
1/7/15
Shortened edge length arrows to indicate length of
table on the inside.
367
1/7/15
Removed diamonds from edges of table.
“x” is not in the
problem. CE, not x.
Lesson 6.1.1 Math
Notes box
Deleted incorrect
definition of congruent.
6-20. (b)
Rigid transformations,
not translations.
6-42.
Updated question in
problem prompt.
6-53.
Updated diagram.
6-54. (b)
Updated diagram.
Errata for Core Connections Geometry
Also updated the resource page.
Page 28 of 37
Problem Number and
Description of Change
6-70. (c)
Page
Number
Date
374
12/8/14
What triangle tool can you use to find the angle of
depression of the path of the ball? Find the acute
angle the path of the ball makes with the ground.
380
3/26/14
If the base angles of a triangle are congruent, then it
is isosceles.
383
2/9/15
Deleted reference to
angle of depression.
6-86. (a)
Typo in problem. Then,
not the.
7-1. (b)
Corrected Version
P
Diagram missing.
C
7-57.
422
6/20/14
425
3/26/14
Updated wording
(equation not
expression).
7-63.
Write an equation for each of the following
sequences.
T
U
b
“c” missing from
diagram.
W
7-92.
a
V
439
1/22/14
m∠PMA = m∠PMB = 90º
455
1/7/15
Graph on ABCD if A(1, 4), B(6, 6), C(4, 1), and
D(–1, –1).
458
5/2/14
Thus, if A(1, 3) and B(5, 8) , then Δx = 5 − 1 = 4 and
Δy = 8 − 3 = 5 . Then the x-coordinate of M is
1+ 12 (4) = 3 and the y-coordinate is 3 + 12 (5) = 5.5 .
So point M is at (3, 5.5).
470
2/1/14
Must be: none; Could be: rectangle, square, isosceles
trapezoid
Typo in “Statements”
column of proof.
7-131. (a)
Deleted the word “on”.
Lesson 7.3.3 Math
Notes box
Incorrect midpoint given
in example.
CL 7-156. (a)
Incorrect answer.
Errata for Core Connections Geometry
Page 29 of 37
Problem Number and
Description of Change
Lesson 8.1.2 Math
Notes box
Page
Number
Date
Corrected Version
481
3/26/14
Rhombus: Since a rhombus is a parallelogram, it
has all of the properties of a parallelogram. In
addition, its diagonals are perpendicular bisectors
that bisect the angles of the rhombus; the
diagonals also create four congruent triangles.
482
2/8/15
All of these are correct
496
3/21/14
A quadrilateral with diagonals that are perpendicular
bisectors of each other.
498
2/7/14
Write down any observations or patterns you found
while working on problem 8-67.
503
2/23/15
His girlfriend decides to divide the cookie into 12
separate but congruent pieces. After 9 of the pieces
have been eaten, what area of the cookie is left?
504
2/8/15
∠ADB ≅ ∠CBD
513
9/8/14
If the length of a side of the polygon is 2 units, what
is the area of the polygon?
514
5/2/14
In Lesson 8.3.2, you developed methods to find the
area and circumference of a circle with
radius r.
517
3/20/14
AC = BC
527
2/8/15
m∠C = 32º
519
2/27/15
If the area of ΔABE is 19 cm2, what is the area of
ΔACD?
Updated wording in
“rhombus” paragraph.
8-23. (e)
Incorrect phrase.
8-61. (d)
Updated wording.
8-68.
Incorrect problem
reference.
8-84. (b)
Updated wording.
8-87.
Typo in middle bubble
of flowchart.
8-107. (b)
Missing the word units.
Lesson 8.3.3
introduction
Incorrect lesson
reference.
8-118.
Statement 4 does not
need segment bars.
CL 8-133. (d)
Typo in answer.
8-125. (b)
Updated problem to
correct area of triangle.
Errata for Core Connections Geometry
Page 30 of 37
Problem Number and
Description of Change
CL 8-136. (a)
Page
Number
Date
525
4/28/15
Corrected Version
2x + 50º
Impossible quadrilateral
in diagram.
3x + 25º
x = 25º
8-138. (e)
525
10/28/15 e.
Updated wording.
CL 8-139. (b)
528
2/8/15
553
4/6/14
Updated answer.
9-64. (d)
Typo in last sentence.
∠CAD not ΔCAD.
m = 50º, supplementary angles
i = 51º, Triangle Angle Sum Theorem
uuur
That is, find AD such that ∠BAD ≅ ∠CAD.
New diagram in which AB = AC.
Updated diagram.
9-101. (d)
Find the measure of an exterior angle of a
regular polygon with 10 sides.
=
567
9/8/14
How does this help explain that
593
12/8/14
a. Timothy decided to create two triangles
(ΔBED and ΔAEC).
BP
BE
2
3
?
Last fraction had an
incorrect denominator.
10-27.
Incorrect triangle names.
AEC not ACE.
10-28.
c. How are ΔBED and ΔAEC related?
593
4/17/14
A polygon is said to be inscribed in a circle when
each of its vertices touch the circle.
595
4/29/15
 = 2 p − 2k = 2( p − k) = 2m∠EAC
mEC
596
7/8/14
 and CD
?
a. What is the relationship between AB
How do you know?
 or CD
?
b. Which has greater measure, AB
Typo: its, not is.
Lesson 10.1.3 Math
Notes box
Incorrect formula in
second to last paragraph.
10-32.
Updated wording in
parts (a) and (b).
Which has greater length? Explain.
10-76. (d)
615
Incorrect part reference.
Errata for Core Connections Geometry
12/8/14
Shade the cells in your table from part (b) where a
student has previously taken the folder.
Page 31 of 37
Problem Number and
Description of Change
10-97.
Page
Number
Date
623
4/17/14
Thus, the heights for 175 people randomly selected
people are independent of their IQs.
624
2/8/15
State the Addition Rule.
625
1/22/16
625
4/11/16
Charlie’s neighbor subscribes to at least one paper.
625
11/2/15
The Sunshine Orange Juice Company wants its
product in a one-quart container (1 quart equals
57.75 cubic inches). The manufacturer for their
containers makes cylindrical cans that have a base
that is 5 inches in diameter. What will be the height
of the one-quart container?
635
4/29/15
How many three-number locker combinations
could Carmen make up if zero could only be the
second or third number and none of the numbers can
be repeated?
636
4/17/14
How is this list different from all the arrangements a
child can make on a line on the refrigerator door with
three magnetic letters A, B, and C?
644
2/8/15
For the each of the following expressions, write
down a factorial expression and then compute the
value.
Repeated word.
10-100.
Corrected Version
First bullet should be
singular.
10-102.
Updated art.
10-102. (c)
Updated wording to be
clearer.
10-103.
Incorrect conversion
given.
10-122. (d)
Three-number, not
three-digit.
10-123. (a)
First sentence below box
is a question.
10-141.
Typos in first sentence.
Errata for Core Connections Geometry
Page 32 of 37
Problem Number and
Description of Change
10-150.
Page
Number
Date
648
1/21/14
Updated wording.
Corrected Version
Charlie and his nephew, Jake, who is a bottomless
hunger pit, went to the state fair. Charlie had
promised he would buy Jake three snacks. He
can have one when they arrive, one midafternoon, and one when they were about to
leave, or, as Jake prefers, he can have all of the
snacks all at once. At the food stand the menu
included seven items:
…
Jake likes everything on the menu so much that
he would not mind having any three items or even
any two or three of the same thing. Uncle Charlie
thinks variety is good so he wants Jake to choose
three different things.
10-172. (f)
657
2/8/15
Use a similar method for calculating the probability
of getting two of a kind.
657
2/8/15
What is the probability of getting two pairs?
707
9/8/14
Find the area of a regular decagon if the length of
each side is 20 units.
714
7/8/14
Assume that the radius of the Earth is 4000 miles.
723
5/27/15
Number with primarily birds and under $20,000
should be 9 (not 69).
724
9/8/14
She plans to tie three loops of ribbon about the
package as shown at right.
Two of a kind, not one
pair and then another
pair.
10-172. (g)
Added question.
11-99.
Updated problem
wording.
11-114. (a)
Missing the word “is”.
CL 11-129.
Updated data to sum to
1000.
CL 11-131. (b)
Three, not two.
Errata for Core Connections Geometry
Page 33 of 37
Problem Number and
Description of Change
CL 11-129. (e) and (f)
Page
Number
Date
726
5/27/15
Corrected Version
e: Either sum the appropriate cells:
64+63+9+3+70+66+59+7+3+41+77+82+97
1000
Incorrect answers.
= 64.1%
or use the Addition Rule:
385
386
130
641
1000 + 1000 − 1000 = 1000 = 64.1%
f: P(dog given < $35,000) =
64+66
64+63+9+3+70+66+59+7+3+41 = 33.7%
CL 11-130. (a)
726
4/3/14
ΔABC ~ ΔRTS (AA~)
732
7/8/14
Add a point P to your diagram and then draw a right
triangle like ΔABP in the circle at right.
SB: 11
4/28/15
Example 2:
Calculate the area and perimeter.
Missing parenthesis in
answer.
12-3. (a)
Incorrect triangle
referenced.
Checkpoint 4
Impossible triangle in
Example 2.
HB: 787
9.85 cm
4 cm
5 cm
6 cm
A = 12 bh = 12 ⋅ 6 ⋅ 4 = 12 cm 2
P = 6 + 5 + 9.85 = 20.85 cm
Checkpoint 4
Impossible diagram in
problem #7.
SB: 13,
14
6/1/16
10 ft
10 ft
HB:
789, 790
16 ft
8 ft
12 ft
7.
Errata for Core Connections Geometry
A = 144 ft2, P = 64 ft
Page 34 of 37
Problem Number and
Description of Change
Page
Number
Date
Checkpoint 7
SB: 780
4/28/15
Diagrams in problems 4
and 5 were missing the
parallel marks.
HB: 803
Corrected Version
4.
15
z
4
45°
22
7
5.
y
10
6
17
Checkpoint 8
SB: 793
4/29/15
HB: 806
a: supplementary angles sum to 180º; x = 26º
b: alternate exterior angles are congruent; x = 5º
c: Triangle Angle Sum Theorem; x = 15º
d: exterior angle equals sum of remote interior
angles; x = 35º
Checkpoint 8
SB: 794
Diagrams in first three
practice problems
repeated CL 8-137 and
had incorrect answers.
HB: 807
4/29/15
1.
2.
4x – 2º
3x + 2º
3.
y – 48º
3y
101º
34º
z
Checkpoint 8
SB: 794
4/29/15
Now we can go back
and solve the original
problems work updated.
HB: 807
Checkpoint 8
SB: 795
Ex: (b) 5x + 6º = 2x + 21º
3x = 15º
x = 5º
12/21/15 10.
Impossible triangle in
problem #10.
HB: 808
All work was missing degree symbols.
m + 8º
2m – 3º
Errata for Core Connections Geometry
m + 6º
Page 35 of 37
Problem Number and
Description of Change
Page
Number
Date
Corrected Version
Checkpoint 8
SB: 786
4/28/15
All answers need the
degree symbol. Answer
18 was incorrect.
HB: 809
congruent vertical angles, supplementary same-side
interior; x = 18.5º, y = 22.5º
9-73.
SB: 787
4/29/15
Incorrect tree diagram
answer.
HB: 810
Bread
Protein
Condiment
mayo
salami
plain
mayo
turkey
white
plain
mayo
ham
plain
mayo
salami
plain
mayo
turkey
grain
plain
mayo
ham
Checkpoint 9A
Example 1
SB: 788
plain
9/8/14
First Drink
HB: 811
Incorrect entries in
table.
hot coffee
Second
Drink
Checkpoint 9A
problem 1 (b) answer
SB: 795
9/8/14
0.09 = 9%
9/8/14
≈ 172.0 ft2
hot tea
5
8
2
8
frozen coffee
slush 18
hot
coffee
hot
tea
5
8
2
8
25
64
10
64
10
64
frozen
coffee
slush
5
8
5
64
5
64
HB: 818
Incorrect answer.
Checkpoint 10
problem 11 answer
SB: 804
HB: 827
Incorrect answer.
Errata for Core Connections Geometry
Page 36 of 37
Problem Number and
Description of Change
Page
Number
Date
Checkpoint 11
problem 7 answers
SB: 808
5/27/15
V ≈ 2.362 m 3; SA ≈ 10.85 m 2
4/29/15
Cavalieri’s Principle Two solids have the same
volume if corresponding cross-sectional areas are the
same. For example, an oblique solid has the same
volume as the corresponding right solid with the
same height, as long as all the cross-sections parallel
to the base have the same area.
1/19/16
congruent Two shapes are congruent if there is a
sequence of rigid transformations that carries one
onto the other. The corresponding angles and sides
of congruent polygons have equal measures.
Congruent shapes are similar and have a scale factor
of 1. The symbol for congruence is ≅.
1/19/16
similar figures Two shapes are similar if there is a
sequence of rigid motions, followed by a dilation,
that carries one onto the other. The corresponding
angles of similar polygons are congruent, and the
corresponding sides are proportional. The symbol
for similar is ~ . See also ratio of similarity.
4/29/15
slope angle The acute angle a line forms with the
x-axis on a coordinate graph. Also see slope
triangle.
Corrected Version
HB: 831
Incorrect answers.
Glossary – Cavalieri’s
Principle
SB: 813
HB: 837
Parallel, not
perpendicular.
Glossary – congruent
SB: 815
New definition.
HB: 839
Glossary – similar
figures
SB: 837
HB: 861
New definition.
Glossary – slope angle
SB: 838
New definition.
HB: 862
Errata for Core Connections Geometry
Page 37 of 37