Question

Semi perimeter of equilateral triangle is 45 cm . Find the area of equilateral triangle

Answer 1

semiperimeter of an equilateral triangle , S = 45cm
we know, all sides are equal of an equilateral triangle.
so, a = b = c = k (let)
so, semiperimeter , S = (a + b + c)/2
45 = (k + k + k)/2
45 = 3k/2
k = 30
hence, side length of equilateral triangle is 30cm.
so, area of equilateral triangle, $A=\frac{\sqrt{3}}{4}\times\text{side length}^2$

A = √3/4 × (30)²
= √3/4 × 900
= √3 × 225
= 225√3 cm²

hence, area of equilateral triangle = 225√3 cm²

Answer 2

Answer:

area of equilateral triangle = 225√3 cm²