document.write( "Question 145658: Find the length, to the nearest tenth, of the apothem of a regular octagon whose sides are 10 inches long????? \n" ); document.write( "

Algebra.Com's Answer #106298 by nerdybill(7384) $\"\"$ $\"About$

You can put this solution on YOUR website!
For a detailed explanation of apothem and octagon see:
\n" ); document.write( "http://www.mathsisfun.com/geometry/regular-polygons.html
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\n" ); document.write( "Use radians NOT degrees...
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\n" ); document.write( "Side = 2 × Radius × sin(π/n)
\n" ); document.write( "where
\n" ); document.write( "n = number of sides
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\n" ); document.write( "Stuff in the information from the problem:
\n" ); document.write( "10 = 2 × Radius × sin(π/8)
\n" ); document.write( "5 = Radius × sin(π/8)
\n" ); document.write( "5/sin(π/8) = Radius
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\n" ); document.write( "Then, because
\n" ); document.write( "Apothem = Radius × cos(π/n)
\n" ); document.write( "Apothem = 5/sin(π/8) × cos(π/8)
\n" ); document.write( "Apothem = 5cos(π/8)/sin(π/8)
\n" ); document.write( "Apothem = 5cos(π/8)/sin(π/8) \n" ); document.write( "

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