Question

Sides of a triangle are 70cm,80cm,90cm.Find it's area.

Answer 1

Answer:

$= > s = \frac{70 + 80 + 90}{2} = 120 \: cm \\ \\ area \\ = \sqrt{120(120 - 70)(120 - 80)(120 - 90)} \\ = \sqrt{120 \times 50 \times 40 \times 30} \\ = \sqrt{12 \times 5 \times 4 \times 3 \times {10}^{4} } \\ = {10}^{2} \sqrt{ {12}^{2} \times 5 } \\ = 1200 \sqrt{5} \: {cm}^{2}$