document.write( "Question 67713: how do I find the area of a equilateral triangle by only knowing one side of it which is ten ft. I know this is not where I submit this problem but I have a hard time finding the right place to go thank you \n" ); document.write( "
Algebra.Com's Answer #48171 by ankor@dixie-net.com(22740)\"\" \"About 
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how do I find the area of a equilateral triangle by only knowing one side of it which is ten ft
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\n" ); document.write( "Draw the triangle, draw the height of the triangle which you need to find the area.
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\n" ); document.write( "Notice that it bisects the base giving you 2 right triangles with one side of 5 ft and the hypotenuse of 10. The third side is the height of the triangle, we can find that by using the pythagorean theorem:
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\n" ); document.write( "Let the unknown side be = h
\n" ); document.write( "5^2 + h^2 = 10^2
\n" ); document.write( "25 + h^2 = 100
\n" ); document.write( "h^2 = 100 - 25
\n" ); document.write( "h^2 = 75
\n" ); document.write( "h = SqRt(75)
\n" ); document.write( "h = 8.66 ft
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\n" ); document.write( "Find the area:
\n" ); document.write( "A = .5*b*h
\n" ); document.write( "A = .5*10*8.66
\n" ); document.write( "A = 43.3 sq ft \n" ); document.write( "
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