Answer: 7
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Explanation:
We're given P = 38 and L = 12, so let's replace those letters with those values
P = 2W + 2L
38 = 2W + 2*12
38 = 2W + 24
Now let's isolate W. We do so by first subtracting 24 from both sides. Then we divide both sides by 2
38 = 2W + 24
38-24 = 2W + 24-24 ... subtract 24 from both sides
14 = 2W
2W = 14
2W/2 = 14/2 ... divide both sides by 2
W = 7
