Answer: Approximately 137.74977 square units
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Step-by-step explanation:
We can use Heron's formula to find the area of a triangle when given all three sides.
First we need the semiperimeter
s = semiperimeter
s = (perimeter)/2
s = (a+b+c)/2
s = (28+28+10)/2
s = 33
Now we can compute the area of the triangle.