1. Math Humor Q: What type of figure is like a lost parrot?
A: A polygon!!

2. LT 6.1: Apply Properties and Attributes of Polygons

5. Number of Sides
Name of Polygon 3
How many do you know? 4 5 6 7 8 9 10 11 12 n

6. Number of Sides
Name of Polygon 3
Triangle 4
Quadrilateral 5
Pentagon 6
Hexagon 7
Heptagon 8
Octagon 9
Nonagon 10
Decagon 11
Undecagon 12
Dodecagon n
n-gon

8. Identifying Polygons
Tell whether each figure is a polygon. If it is a polygon,
name it by the number of its sides.

10. Classifying Polygons
Tell whether each polygon is regular or irregular. Tell
whether it is concave or convex.

11. Sum of Interior Angle Measures
Polygon
Number of Sides
Number of Triangles
Sum of Interior Angle Measures
Triangle 3 1
(1) 180˚ = 180˚
Quadrilateral 4 2
(2) 180˚ = 360˚
Pentagon 5
(3) 180˚ = 540˚
Hexagon 6
(4) 180˚ = 720˚
n-gon n
n – 2
(n - 2) 180˚

12. Polygon Angle Sum Theorem
The sum of the interior angle measures of a convex polygon with n sides (n – 2) x 180˚.

13. Example
Find c
8c = 360 c = 45 P R S Q c˚
3c˚

14. Polygon Exterior Angle Sum Theorem
The sum of the exterior angle measures,
one angle at each vertex, of a convex
polygon is 360˚.

15. Example
Find the angles
18a = 360 a = °, 60°, 120°, 40°

16. Example Find the following for a regular convex nonagon:
Sum of the interior angles
1260°
Each interior angle
140°
Sum of the exterior angles
360°
Each exterior angle
40°