Question 503679
L = length of the cardboard
The cardboard is square
L^2 = area of the cardboard
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L -4 = length of the sides of the square box made from the cardboard.
It is L-4 because you have to cut a 2x2 square from each corner to make the box.
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Volume of the box = 72 cubic in.
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V = (L-4)*(L-4)*2
V = 72
(L-4)^2 = 36
L-4 = 6
L = 10
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So, the cardboard square originally had sides = 10 inches.
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Done.