IntGeom11.4.notebook
April 25, 2017
11.4 Areas of Regular Polygons A = 1/2 a p
kaleidoskope
A = 1/2 (apothem)(perimeter)
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IntGeom11.4.notebook
April 25, 2017
11.4 Finding the Area of a Regular Polygon
The center of a regular polygon is the center of the
circumscribed circle.
The radius of a regular polygon is the distance from the
center to a vertex.
A central angle of a regular polygon is an angle formed by
two radii drawn to consecutive vertices
The apothem of a regular polygon is the (perpendicular)
distance from the center of the polygon to a side.
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IntGeom11.4.notebook
April 25, 2017
Area = 1/2 a p
a = apothem
p = perimeter
Example: Square
r=
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IntGeom11.4.notebook
April 25, 2017
Area = 1/2 a p
Example: Equilateral triangle
r=6
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Area = 1/2 a p
Example: Regular Hexagon
a=
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IntGeom11.4.notebook
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Example: Regular Pentagon
s=8
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pg. 437: #30
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April 25, 2017
Page 443
1.
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IntGeom11.4.notebook
April 25, 2017
Homework for tonight:
pg. 443: 1-16 (wr) and #9 (cl)
and pg. 444 (s.t. #1) 1-10
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