SOLUTION: How do you find the area of an equilateral triangle if the perimeter is 18cm?

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Question 826800: How do you find the area of an equilateral triangle if the perimeter is 18cm?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
each side is 6
drop a line from the top angle to the base forming a right triangle with base 3 and hypotenuse 6
and the height is 3 sqrt(3)
3^2+h^2=36
h^2=27
h^2=3*9
h=3sqrt(3)
1/2 b*h=1/2*3*3*sqrt(3)
9/2 sqrt(3)