Solve for r
r=4
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12r-25-4r=7
Subtract 4r from both sides.
8r-25=7
Combine 12r and -4r to get 8r.
8r=7+25
Add 25 to both sides.
8r=32
Add 7 and 25 to get 32.
r=\frac{32}{8}
Divide both sides by 8.
r=4
Divide 32 by 8 to get 4.
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