You can put this solution on YOUR website! find the side length of a 15-sided regular polygon with apothem a=6 and area A= 282 square inches.
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Central angle = 360/15 = 24 degs
Each of the 15 segments can form 2 right triangles with the apothem and the side, and the angles at the center are 1/2 of 24 deg = 12 degs.
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(s/2)/a = tan(12)
s = 2*a*tan(12)
s =~ 2.5507
