1. Classifying polygons
Chapter 1

2. Homework Quiz!
Angle 1 and angle 2 are supplementary. The measure of angle 1=97°, find the measure of angle 2.
Angle 3 and 4 are complementary. If the measure of angle 3=74°, find the measure of angle 4.
Find the measure of angle EFH.

3. Identifying Polygons
A polygon is a closed figure with the following properties:
It is formed by three or more line segments called sides.
Each side intersects exactly two sides, one at each endpoint.
Each endpoint of a side is called a vertex of the polygon. Multiple vertex are called vertices.
We name polygons by listing the vertices

4. Convex and Concave
Convex: no line that lies on a side of the polygon contains a point in the interior of the polygon
Concave: a line that lines on the side of the polygon contains a point in the interior of the polygon (not convex)

5. Decide whether each figure is a polygon
Decide whether each figure is a polygon. If it is, is it convex or concave? 1 3 2 4

6. Classifying Polygons
We name polygons based on the number of its sides:

7. N-gons
The term n-gon, where n represents the number of a polygon’s sides, can also be used to name a polygon
Example: a polygon with 14 sides is a 14-gon

8. Types of Polygons Equilateral polygon: all sides congruent
Equiangular polygon: all angles in the interior are congruent
Regular polygon: convex polygon that is both equilateral and equiangular

9. Explain whether the polygon is equilateral, equiangular, or regular1. 3. 2.

10. Sketch an example of a convex heptagon and an example of a concave heptagon.

11. Finding side lengths
A table is shaped like a regular hexagon. The expressions shown represent side lengths of the hexagonal table. What is the length of each side?
(3x+6) in
(4x-2) in

12. Things to remember A polygon is formed by _________ or more lines.
Convex:
Concave:
Regular: