You can put this solution on YOUR website! s=4lw+2wh
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Is it 4LW ?
Or 41W ?
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That's the only possible L, must be it.
All you can do is isolate the L, get it one side of the equal sign by itself.
S = 4LW + 2WH
S - 2WH = 4LW
4LW = S - 2WH
L = (S - 2WH)/4W
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How could you get 48?