An equilateral triangle has an altitude of 15m. What is the perimeter of the triangle?

1 Answer
Apr 1, 2018

303=51.9615 meters

Explanation:

In an equilateral triangle, all sides are equal and all angles are 60 degrees. This means that if you cut the triangle in half by the altitude(also the height in an equilateral triangle), you get 2 306090 triangles(those are the angle measures). These triangles have the relationship:
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The 15 meter height is the x3 side. To find x, divide by 3.

15331533=53

x=53, so 2x=103

That is one side of the equilateral triangle, and 1033=303.

That is the perimeter.