Question 865319
Find the area of an equilateral triangle (regular 3-gon) with the given measurement.

9-inch perimeter --> sides = 9/3 = 3
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Area of a regular polygon with n sides of length s is
{{{Area = ns^2*cot(180/n)/4}}}
{{{Area = 3*3^2*cot(60)/4}}}
{{{Area = (27/4)*sqrt(3)/3}}}
=~ 1.299 sq inches