Chapter 2
Investigating Geometric Figures
2-2 POLYGONS
Objective: Classify polygons; find
the sum of the measures of the
interior and exterior angles of
polygons
Sum of int <s =
One int < =
Regular
Sum of ext <s =
One ext < = Regular
The measure of an interior angle of a regular polygon
is 144°. Find the number of sides.
pg. 80 # 1­4, 10 – 17, 19 – 26
1. Convex dodecagon
2. Concave decagon
3. Convex octagon
4. Concave pentagon
10. 108;72
11. 140;40
12. 160;20
13.
14. 5
15. 10 13.
16. 20
17. 19. 102
20. 145
21. y = 103
22. 103
w = 111
z = 70
24. 60
23. x = 69
25. 113
26. w = 72, x = 59
y = 49, z = 121
Algebra Review­­Graphing Lines
y = mx + b
HW # 19
Practice 2­2 Study for Quiz .
Quiz Review 2.1 - 2.2
-- Triangle-Sum Thm
-- Exterior Angle Thm
-- Classifying Triangles
-- Naming Polygons
-- Concave, Convex, Regular
-- Polygon Formulas Interior/Exterior
**** Must Know
Find y and z.
76°
41°
z°
y°
Find a, b, c, d.
71
d
a
21
b
c
33
What is the
equation of this line?