Question

Heron’s formula: Area = Triangle PQR has sides measuring 9 feet and 10 feet and a perimeter of 24 feet. What is the area of triangle PQR? Round to the nearest square foot.

Answer 1

The answer is 22 square feet. I just took the practice.

Answer 2

Hello,

Let's assume a,b,c the 3 sides of the triangle.

a=9
b=10
c=24-a-b=5

$p= \dfrac{a+b+c}{2} =12\\ S= \sqrt{p(p-a)(p-b)(p-c)} = \sqrt{12*3*2*7} = \sqrt{504} =22,4499...\approx{22}$