Mark M. answered • 01/28/15

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Draw a picture

After cutting out a square that is x by x from each corner, the base is 10 - 2x by 10 - 2x

48 = (10 - 2x)(10 - 2x)x

48 = (100 - 40x + 4x

^{2})x48 = 100x - 40x

^{2}+ 4x^{3}0 = 4x

^{3}- 40x^{2}+ 100x - 48Descartes Rule of Signs indicates three real roots, or one real root and two complex roots (this is the one I suspect)

Using the Rational Root Theorem and Synthetic Substitution,

I found x = 3.