SOLUTION: find the area of an equilateral triangle with side length of 12cm

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Question 454527: find the area of an equilateral triangle with side length of 12cm
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
The altitude of equilateral triangle is a perpendicular bisector. Using the Pythagorean Theorem we find out the altitude.
h%5E2=12%5E2-6%5E2, where h is the altitude. h=sqrt%28108%29=6sqrt%283%29cm.
To find the area we use the formula:A=%281%2F2%29b%2Ah, where b is the side length.
A=%281%2F2%2912%2A6sqrt%283%29=36sqrt%283%29cm%5E2