Question 1101217
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The area of a triangle is one-half the base times the height.<br>
In a regular polygon with n sides, if you picture it as n congruent isosceles triangles, the apothem is the height of each triangle, and the perimeter of the polygon is the sum of the bases of all the triangles.<br>
So the area of a regular a regular n-gon with apothem 12 and perimeter 81.6 is {{{(1/2)(81.6)(12) = 489.6}}}