Download 8IndGeoTest_A practice WITH KEY

CPM Geometry
Practice Chapter 8 Individual Test
Name __________________________
1. a. Find the sum of the interior angles of an octagon.
b. a pentagon
2. a. Find the measure of each interior angle of a regular octagon.
b. pentagon
3. A regular polygon has an interior angle of 150°.
a. How many sides does the polygon have?
b. What is the sum of the interior angles?
c. What is the sum of the exterior angles?
4. Solve for x in the figure below.
d. What is the measure of each exterior angles?
5. The figures below are similar. (PQR ~ XYZ)
a. What is the similarity ratio of the sides?
142
(x - 5)
x
a.
x
x+3
of the perimeters?
b. What is the ratio of the areas?
c. The area of PQR is 24 units². What is the area of XYZ?
d. If this was a solid, what would the ratio of volumes be?
Y
Q
15
P
6. Find the area and circumference of the circle.
Area = _________________
12 ft
4
R
X
5
Circumference =__________
Z
7. A regular octagon has a side length of 16cm and center at point O. Find the following.
a. Central Angle AOB = _____________
b. Perimeter = _____________
c. Area of triangle AOB =______________
d. Area of polygon =______________
8. A circle has a circumference of 32π ft.
a. What is the circle’s radius?
b. What is the circle’s area?
9. A sector has a central angle of 120o and r =4in.
a. Find the area.
b. Find the arc length
10. Solve for x in the diagram.
11. Given isosceles triangle ABC with AB = AC (mark diagram).
a. Find the measure of angle A.
b. Does that answer made sense? Explain.
78°
A
x
39°
x + 40
B
2x +60
C
12. Solve for x in the diagram.
x
43
18
13. Find the midpoint of AB given A(-8, -23) and B(12, -21):
14. a. Find x.
b. Find the measure of each angle.
15. On a standard 6 sided die, what is the
probability of
C
5x+20
3x+40
A
B
D
a. rolling a number greater than 3?
b. rolling an even number?
c. rolling a prime number?
d. rolling a factor of 12?
e. rolling a 2 or 6?
f. rolling a 7 or 4?
CPM Geometry--KEY
Practice Chapter 8 Individual Test KEY
KEY
1a. Find the sum of the interior angles of an octagon.
(8-2)180o=1080o
b. a pentagon
(5-2)180o=540o
2a. Find the measure of each interior angle of a regular octagon. b. pentagon
o
o
1080o
540o
8  135
5  108
3. A regular polygon has an interior angle of 150°.
a. How many sides does the polygon have?
b. What is the sum of the interior angles?
360o
b. (12 - 2)180o  1800o
30  12 sides
c. What is the sum of the exterior angles?
d. What is the measure of each exterior angles?
o
o
o
c.360 always
d . 360
12  30
4. Solve for x in the figure below.
5. The figures below are similar. (PQR ~ XYZ)
a. What is the similarity ratio of the sides? of the perimeters?
4
5
142
b. What is the ratio of the areas?
2
 54   1625
(x - 5)
b.
4
5
x
c. The area of PQR is 24 units². What is the area of XYZ?
16
24
25  x
x
x+3
x  37.5un 2
d. If this was a solid, what would the ratio of volumes be?
3
64
 54   125
Y
90o  xo   x  3  xo   x  5  142o  720o
o
o
Q
x  122.5o
15
P
6. Find the area and circumference of the circle.
Area = _________________
12 ft
4
R
X
5
Circumference =__________
A   r2
C  2 r
  122
 144 ft
 2 12
2
 24 ft
 452.4 ft
 75.4 ft
2
Z
7. A regular octagon has a side length of 16cm and center at point O. Find the following.
a. Central Angle AOB =
360o
8
P  add all sides
b. Perimeter =  8(16)
 45
o
 128cm
7d. Apoly  12 aP
7c. A  12 bh
 12 16(19.3)
c. Area of triangle AOB =
154.5cm2
 1236.1cm 2
or 5* Area triangle
8. A circle has a circumference of 32π ft.
a. What is the circle’s radius?
C  2 r
b. What is the circle’s area?
b. A   r 2
32  2 r
A  256
16 ft  r
9. A sector has a central angle of 120o and r =4in.
a. Find the area.
A  centralangle
 r2
360o
A  804.2 ft 2
b. Find the arc length
b. AL  centralangle
2 r
360o
A  120
 42
360o
AL  120
2 4
360o
A  16.8in 2
AL  84.2in
o
o
10. Solve for x in the diagram.
11. Given isosceles triangle ABC with AB = AC (mark diagram).
a. Find the measure of angle A.
b. Does that answer made sense? Explain.
o
o
a.  x  40    2 x  60 
A
78°
x  20
x
b. yes, mB & C = 20o
39°
180o  (78o  39o )  63o
180  63  117
o
o
x
43
12.  8212 , 232 21 
 2, 22 
x  13.2un
14. a. Find x.
b. Find the measure of each angle.
C
5x+20
3x+40
D
B
14. 3 x  40  5 x  20  180
8 x  120
x  15
C
13. Find the midpoint of AB given A(-8, -23) and B(12, -21):
11.cos 43o  17x
18
2x +60
x + 40
B
o
12. Solve for x in the diagram.
A
 12 19.3 128 
d. Area of polygon =
15. On a standard 6 sided die, what is the probability of
a. rolling a number greater than 3?
b. rolling an even number?
c. rolling a prime number?
d. rolling a factor of 12?
e. rolling a 2 or 6?
f. rolling a 7 or 4?
15a. 12 15b. 12 15c. 12
15d .
5
6
15e.
2
6
15 f . 12