SOLUTION: the perimeter of an equilateral triangle is 39 cm. find the length of an altitude of the triangle

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Question 542076: the perimeter of an equilateral triangle is 39 cm. find the length of an altitude of the triangle
Answer by stanbon(75887) About Me  (Show Source):
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the perimeter of an equilateral triangle is 39 cm. find the length of an altitude of the triangle
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Draw a picture of an equilateral triangle.
Draw an altitude (which is a perpendicular bisector of the base).
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Use Pythagoras to find the altitude:
h^2 + (39/2)^2 = 39^2
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h^2 = (3/4)39^2
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h = (39/2)sqrt(3) cm
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Cheers,
Stan H.
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