1. Section 11-4 Areas of Regular Polygons

2. Given any regular polygon, you can circumscribe a circle about it.

4. Center of a regular polygon is the center of the circumscribed circle Example:

5. Radius of a regular polygon is the distance from the center to a vertex Example:

6. Central angle of a regular polygon is an angle formed by two radii drawn to consecutive vertices. Example:

7. To find the Measure of a Central Angle of a Regular Polygon: **n = the number of sides = Central Angle

8. 1

9. Find the measure of a central angle for each inscribed figure. 1.A square 2.A regular octagon 3.A regular pentagon 4.A regular Decagon

10. apothem of a regular polygon Is the (perpendicular) distance from the center of the polygon to a side. Example:

11. Theorem 11-6 The area of a regular polygon is equal to half the product of the perimeter and the apothem.