Can you please answer the 42nd question - Maths - Perimeter and Area

Question

Can you please answer the 42nd question

Deepika Sharma · Accepted Answer

Dear Student

By Heron's formula,

Area of Equilateral Triangle = $\sqrt{s (s - b) (s - b) (s - b)}$

Where S is semi perimeter of triangle and is given by –

$S = \frac{b + b + b}{2} = \frac{3 b}{2}$

$∴ Area of Equilateral Triangle = \sqrt{\frac{3 b}{2} (\frac{3 b}{2} - b) (\frac{3 b}{2} - b) (\frac{3 b}{2} - b)} = \frac{\sqrt{3} b^{2}}{4} Square Units.$

Use this formula to find your answer.

here b = 15 cm

Answer will be approx 97.43 cm^2.

Post again in the forum in case you face any problem.

Regards