SOLUTION: An equilateral triangle has side lengths of 15. What is the length of its altitude?

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Question 954618: An equilateral triangle has side lengths of 15. What is the length of its altitude?
Answer by lwsshak3(11628) About Me  (Show Source):
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An equilateral triangle has side lengths of 15. What is the length of its altitude?
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Draw a line from any apex perpendicular to the side opposite.
You now have a right triangle with hypotenuse=15 and one of the legs=7.5 (half a side)
Solve by pythagorean theorem:
altitude=√((15^2)-(7.5^2))√(225-56.25)=√168.75=12.99