Question

A traffic signal board, indicating 'SCHOOL AHEAD”, is an equilateral triangle with
1.
side .a'. Find the area of the signal board, using Heron's formula. If its perimeter is
11
180 cm, what will be the area of the signal board?​

Answer 1

Answer:

Given Perimeter =180 cm

Semi-perimeter s=2180

s=90 cm

Since all sides of equilateral triangle are equal

So,

Perimeter =180

a+a+a=180

3a=180

a=60 cm

Area of triangle =s(s−a)(s−b)(s−c)

                           =90(90−60)(90−60)(90−60)

                           =90×30×30×30

                           =(9×3×3×3)×(10)4

                           =(92)×3×(10)4

                           =9×3×(10)2

                           =9×100×3

                           =9003