Question

13. If its perimeter of an equilateral triangle is 180 cm, what will be its area?​

Answer 1

=sum of all sides

=180+180+180

=540cm

Answer 2

Let a be side

So, 3a=180 cm⟹a=60 cm

$Area = \frac{ \: \sqrt{3} \: }{4} {a}^{2}= \frac{ \: \sqrt{3} \: }{4} \times {60}^{2} = 900 \sqrt{3} \\ Area=1558.84  {cm}^{2}$