Answer: A) 52 square inches
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Step-by-step explanation:
a = 8, b = 13, and c = 15 are the sides of the triangle
s = (a+b+c)/2 = (8+13+15)/2 = 18 is the semi-perimeter, aka half the perimeter.
Those values are then plugged into Heron's Formula below
The triangular plaque has an area of approximately 52 square inches.