Question 209082
Volume  =84  = L*W*H = L*(L-3)*(3)= 3L^2 -9L
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3L^2 -9L -84 =0,,,,,divide  by  3
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L^2 -3L-28 = 0
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(L-7)(l+4) =0
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L=7,,-4,,,not  realistic
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check, L=7,,,,H=7-3=4,,,W=3,,,,,Vol = 7*4*3 =84,,,ok
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