<PRE><B>Question 174483</B>
2L +2w=4(L-w+7)
2L + 2w = 4L - 4w + 28


In order to solve for the variable L, you must get all the L terms to one side.  I recoommend to subtract 2L from each side, leaving 
2w = 2L - 4w + 28


Next add +4W and -28 to each side:
2w + 4w - 28 = 2L
6w - 28 = 2L


Finally, divide both sides by 2:
L = 3W - 14


R^2
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