SOLUTION: If the altitude of an equilateral triangle is 5cm, what is the length of a side?

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Question 482437: If the altitude of an equilateral triangle is 5cm, what is the length of a side?
Answer by cleomenius(959) About Me  (Show Source):
You can put this solution on YOUR website!
This becomes a 30-60 90 right triangle, we are looking for the side opposite the 90 degree angle, or the hypotenuse.
So, the hypotenuse will be s, and the formula for the side opposite 60 degree angle, which is the value we are given as 5, is s = ssqrt%283%29/2.
This works out to s = 10sqrt%283%29/3. This is our answer.
To check, multiply 10sqrt%283%29/3 by sqrt%283%29/2.
This confirms to 5, the value we had been given.
Cleomenius.