SOLUTION: what is the area of an equilateral triangle with side lengths of 3?

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Question 197568: what is the area of an equilateral triangle with side lengths of 3?
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
what is the area of an equilateral triangle with side lengths of 3?
.
Area of triangle = (1/2)bh
where
h is height
b is base (3)
.
Calculate height using Pythagorean theorem:
Let h = height
h^2 + (3/2)^2 = 3^2
h^2 + (9/4) = 9
h^2 = 9 - 9/4
h^2 = 36/4 - 9/4
h^2 = 27/4
h = +3%2F2+%2A+sqrt%283%29
.
Plugging it all back into:
Area of triangle = (1/2)bh
Area of triangle = %281%2F2%29%283%29%283%2F2+%2A+sqrt%283%29%29
Area of triangle = %289%2F4%29%28sqrt%283%29%29