If the perimeter of an equilateral triangle is 30 ft, what is the area?
25√2 sq. ft.
25√3 sq. ft.
50√3 sq. ft.

Question

If the perimeter of an equilateral triangle is 30 ft, what is the area?
25√2 sq. ft.
25√3 sq. ft.
50√3 sq. ft.

mathmale · Answer

If the perimeter of the equilateral triangle is 30 ft., then each side has what length?

What is the formula for the area of a triangle?

This formula involves an expression for the height (h) of the triangle.  Since the triangle is equilateral, the angles are all the same.  Use this fact to derive an expression for the height, h, of the triangle, given that the base is b.

Substitute this result into the formula for the area of a triangle and evaluate the area for side length 10 ft.

anonymous · Answer

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