Question

In ΔPQR, p = 13 inches, q = 18 inches and r=12 inches. Find the area of ΔPQR to the nearest square inch.

Answer 1

Explanation:

First....is it a RIGHT triangle ?

does 18^2 = 13^2 + 12^2 ? No, it does not

so you will need to use Heron's formula for triangle area given only the side lengths

AREA = sqrt ( s (s-a)(s-b)(s-c))

where s = ( 13 + 18 + 12 ) / 2 = 21.5

Area = sqrt ( ( 21.5 ( 21.5-13)(21.5-18)(21.5-12) ) = 77.95 = ~ 78 in^2