SOLUTION: Find the area of an equilateral triangle (regular 3-gon) with the given measurement. 9-inch perimeter A = sq. in.

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Question 865319: Find the area of an equilateral triangle (regular 3-gon) with the given measurement.
9-inch perimeter
A = sq. in.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
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%5E2%2Acot%28180%2Fn%29%2F4
Area+=+3%2A3%5E2%2Acot%2860%29%2F4
Area+=+%2827%2F4%29%2Asqrt%283%29%2F3
=~ 1.299 sq inches