Question

There is slide in a park .One of its side walls has been painted in some colour with a message " Keep the park green and clean " . lf the side of the wall are 15 m, 11 m, and 6 m , find the area painted in colour ?​

Answer 1

Answer :-

• Area if painted wall = 20√2 cm

Given :-

• Length of first side = 15 metres
• Length of second side = 11 metres
• Length of third side = 6 metres

To Find :-

• The area of Painted wall.

Explanation :-

As we know, by using Heron's Formulae we need semi-perimeter of triangle or triangular object.

Finding Semi-perimeter of wall

$\implies \rm \dfrac{Side \: 1 + Side \: 2 + Side \: 3}{2}$

$\implies \rm \dfrac{15 + 11 + 6}{2}$

$\implies \rm \dfrac{32}{2}$

$\boxed { \implies \rm \bold { 16 \: cm}}$

Now, Substituting the values

$\implies \rm \sqrt{s (s - a) (s - b) (s - c)}$

$\implies \rm \sqrt{16 (16 - 15) (16 - 11) (16 - 6)}$

$\implies \rm \sqrt{16 (1) (5) (10)}$

$\implies \rm \sqrt{16 \times 1 \times 5 \times 10}$

$\implies \rm \sqrt{800}$

$\underline { \boxed { \implies \rm \bold { 20 \sqrt{2} \: cm^2 }}}$

Hence, the area of painted wall is 20√2 cm²