Download polygon - Shope-Math

Honors Geometry 18 Oct 2011
Take papers from your folder and put them in your binder.
Place your binder, HW and text on your desk.
Warm-up- silently please  (use 1 sheet for week)
Sketch the figure on your warm up paper and answer
the questions using proper naming.
finished? try doing the “line design” on your calculator page- 134
Objective
Students will define and classify triangles and
apply definitions to solve problems.
Students will take notes, participate in a white
board review and use think-pair-share as they
complete problems.
A good definition
CLASSIFIES and DIFFERENTIATES
A ________ is a _________(what) that or in
which________________________.
ex: A SQUARE is a polygon that has 4 congruent
sides and 4 90⁰ angles.
lastly? check for counterexamples
Homework due today
1) DO INVESTIGATION on Triangles, pg. 60 – 61
you need to sketch the examples and non-examples
and write your definitions for SIX TERMS
2) DO PAGE 62, # 1 – 10
Check your answers √ or X each problem
CHAT WITH YOUR GROUP
can you find any counterexamples?
Refine your definitions if needed
Homework due next class
Geometry assumptions
You MAY assume:
Lines are straight and that if they intersect
they intersect at one point
Points on a line are collinear and that all points
in a diagram are co-planar unless the drawing
indicates they are not.
you may NOT assume that:
• Just because two lines LOOK parallel that they
ARE parallel unless they are marked or have
angle measures indicating they are
• Just because two lines LOOK perpendicular
that they ARE perpendicular unless they are
marked or angle measures indicate they are
• pairs of angles, segments, polygons are
congruent unless they are marked with
information that shows you that they are
POLYGONS
add to your vocab section
WORD
DEFINITION
POLYGON
side
diagonal
vertices
closed figure in a plane
formed by connecting line
segments endpoint to
endpoint with each
segment intersecting
exactly two others.
CONVEX polygon
no diagonal outside the
polygon
CONCAVE polygon
at least one diagonal is
outside the polygon
Perimeter
the sum of the length of
the sides
SKETCH and/or example
add to your vocabulary section
Term
Definition
Right Triangle
Has one right angle
Acute triangle
Has three acute angles
Obtuse
triangle
Has one obtuse angle
Scalene
triangle
Has no congruent sides
Equilateral
triangle
Has three congruent sides
Isosceles
triangle
Has at least two congruent
sides
(all three sides have different
measurements)
Example- ADD
MARKINGS
Triangles
Name the triangle:
13
7
8
Congruent:
Name the triangle that is congruent to …
N
NEW  ?
D
W
O
E
L
The perimeter of ABCDE is 94 m. Find the lengths
of segments AB and CD
C
D
X 3
16
B
A
X 8
E
B
a) Mark the figure to indicate the given information:
AB  CB
mA  mC
A
C
B) Copy the figure then mark it to indicate the given information:
1) Point E is the midpoint of
2)
3)
CDB
BF
C
CB
is a right angle
is an angle bisector
E
F
A
D
B
debrief
what did you learn today?
what was easy? what was difficult?
what can I do to help you?