Question 1138821
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The three side lengths are 12 ft, 16 ft and 20 ft.


It is a standard (3,4,5) right angled triangle.


Formally and algebraically


x^2 + (x+4)^2 = (x+8)^2     (Pythagorean with x = the length of the shortest leg)


x^2 + x^2 + 8x + 16 = x^2 + 16x + 64


x^2 - 8x - 48 = 0


(x-12)*(x+4) = 0


x= 12 is the only positive solution.
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