Question 976475
The side measures are 13 mi, 16mi , 18mi
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You can solve for an angle using the Cosine Law, then Area = b*h*sin(angle) where the angle is between the 2 sides.
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Or use Heron's Law:
Area = {{{sqrt(s*(s-a)*(s-b)*(s-c))}}} where a, b & c are the sides and s = (a+b+c)/2