alleryThe area of the triangle with vertices $(3,8)$, $(-4,2)$ and $(5,1)$ is:
A15.25 sq units
B30.5 sq units
C25 sq units
D61 sq units
Answer & Solution
Correct answer: B. 30.5 sq units
Area = ½|3(2−1) + (−4)(1−8) + 5(8−2)| = ½|3 + 28 + 30| = ½·61 = 30.5 sq units.
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