Question

Find the area of an equilateral triangle (regular 3-gon) with the given measurement.

Answer 1

Using Heron's formula where s = 9 ...... and a = b = c = the side lengths .....we have......

A = √[s(s -a)^3] = √[4*3^3] = √[4*27] = √[4*9*3] = √[36*3) = 9√3 sq. in.