Find the area of the triangle with side lengths 4, 5, and 8.
I've always been sort of partial to Heron's formula.
Area = sqrt[(s)(s–a)(s–b)(s–c)] where s = (1/2)(a+b+c)
s = (1/2)(17) = 8.5 therefore A = sqrt(8.5 x 4.5 x 3.5 x 0.5)
A = sqrt(66.9375)
A = 8.1815
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