Question 165074
    r=2n+2w solve for n
.
First, subtract 2w from both sides:
r=2n+2w
r-2w = 2n+2w-2w
r-2w = 2n
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Now, divide both sides by 2:
(r-2w)/2 = (2n)/2
(r-2w)/2 = n
Or,
r/2 - w = n