center vertexcenter

midpoint perpendicular

ap12

perimeter

apothem

Practice p619 #14, 16, 19, 20, 32, 33, 47 [21] p626 #11, 14, 17, 18, 21, 23, 24, 35p631 #1, 5, 8­10

100 in2

1: 120

2: 60

3: 30

4: 90

5: 45

6: 45

7: 60

8: 30

9: 60

10­3 Area of Regular Polygons

What is a "Regular" Polygon?

Equilateral AND Equiangular

10­3 Area of Regular Polygons

Radius: Center to Vertex

Apothem: Center to Midpoint

Central Angle

(n-2)180n

360n

45­45­9030­60­90

Trig

Interior Angle Central Angle

(n-2)180n

360n

45­45­9030­60­90

Trig

Interior Angle Central Angle

(n-2)180n

360n

45­45­9030­60­90

Trig

Interior Angle Central Angle

(n-2)180n

360n

45­45­9030­60­90

Trig

Interior Angle Central Angle

ap12A = B ap1

2=

ap12B =

Find the area of the regular polygon with the given apothem a and side length s.

dodecagon, a = 26.1 m, s = 14 m

ap12B =

ap12B =

Find the area of the regular hexagon. Leave your answer in simplest radical form.

6 m

Find the area of the regular triangle. Leave your answer in simplest radical form.

2√ 3 mm

ap12B =

B

ap12B =

Find B, the area of the Base of this pyramid

ap12B =

Practice p632 #11­13, 17, 18, 21­23, 35, 44, 45

p638 #1, 2