SOLUTION: The length of a side in an equilateral triangle is 5 inches. Find the area of the triangle.

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Question 416351: The length of a side in an equilateral triangle is 5 inches. Find the area of the triangle.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

The length of a side in an equilateral triangle is 5 inches. 

Find the area of the triangle.

A = (1/2)b*h  where h = sqrt%2825-%282.5%29%5E2%29 using the Pythagorean Theorem

     A = (1/2)* 5in *sqrt%2825-%282.5%29%5E2%29 = 10.8253in^2



Checking our answer using the Heron's Equation:

sqrt%28s%28s-a%29%28s-b%29%28s-c%29%29 where a,b,c are the lengths of the sides and s is the semi-perimeter

sqrt%287.5%282.5%29%5E3%29 = 10.8253in^2