Question

12. The sides of a triangle are in the ratio of 3:5:7 and its perimeter is 300 m. Find its area.​

Answer 1

Answer:

Solution:-

Perimeter of triangle = Sum of all sides

300m = 3x + 5x + 7x

300m = 15x

300/15 = x

20m = x

3x = 3 × 20m

= 60m

5x = 5 × 20m

= 100m

7x = 7 × 20m

= 140m

Now find the area of triangle by Heron Formula.

$s = \frac{sum \: of \: all \: sides}{2}$

$s = \frac{300cm}{2}$

$s = 150cm$

$area \: of \: triangle \: = \: \sqrt{s(s - a)(s - b)(s - c)}$

$= \sqrt{150(150 - 60)(150 - 100)(150 - 140)}$

$= \sqrt{150 \times 90 \times 50 \times 10}$

$= \sqrt{3 \times 5 \times 10 \times 3 \times 3 \times 10 \times 5 \times 10 \times 10}$

$= 3 \times 5 \times 10 \times 10 \times \sqrt{3}$

$= 1500 \sqrt{3} \: {cm}^{2}$

Step-by-step explanation:

Hope this helps you.

# By Sparkly Princess