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.

Divide the perimeter by 3 to find the side length.

Since the formula for the are of a triangle is

1/2 * b * h the height must be found.

If a perpendicular line is drawn from the apex of the triangle, a right triangle is formed with a base of 5 and a hypotenuse of 10. Also since it originally was equilateral the base angle is 60 degrees. The rules for finding lengths of sides of equal. Triangles is long leg = sqrt3 * short leg

the height is the long leg so the height is 5sqrt3.

A = (1/2) (10) (5sqrt3) = 25sqrt3