1. 9-2 Area of Regular Polygons The center of a regular polygon is equidistant from its vertices. Radius- the distance from the center to a vertex. Apothem- the distance from the center to a side (must make a 90° angle). apothem radius

2. Formula Area of a regular polygon: where a = apothem and P = Perimeter

3. Example What is the area of a regular octagon with side length s = 5 and apothem a = 2.

4. What is the area of a regular pentagon if the length of each side is 4 inches? 4 in 2 in a a 360÷5= 72° 2 in a 36°