Question

Perimeter of a square is equal to the perimeter of an equilateral triangle whose one side is 12 cm long. the ara of square is :

• A. $144c{m}^2$
• B. $81c{m}^2$
• C. $64c{m}^2$
• D. $100c{m}^2$

Answer 1

Answer: (B)

$81c{m}^2$

Given perimeter of square is equal to perimeter of

equilateral triangle.

and length of one side of eq.$\Delta =12cm$

30 perimeter of $\Delta =3\times 12=36cm$

let square has side a then

4a=36

$[a=9cm]$

now area of square $=a^2=81c{m}^2$