1. Area of Regular Polygons and Circles
10-5
Area of Regular Polygons
and Circles
Objectives:
To find area of regular polygons.
To find the area of circles.

2. Vocabulary
Apothem

3. Apothem
A segment drawn from the center of a regular polygon perpendicular to a side is called an apothem.

4. Area of a Regular Polygon
If a regular polygon has an area of A square units, a perimeter of P units, and an apothem of a units, then s a

5. Example 1
Find the apothem, area, and perimeter of each regular polygon. Round to the nearest tenth.

6. Example 2
Find the apothem, area, and perimeter of each regular polygon. Round to the nearest tenth.

7. Example 3
Find the apothem, area, and perimeter of each regular polygon. Round to the nearest tenth.

8. Example 4
Find the area of the figure. Round to the tenths place if needed.
Perimeter = 40

9. Area of a Circle
If a circle has an area of A square units and a radius of r units, then r

10. In Class Examples

11. Homework
10-5 Worksheet