Solve for r
r=7
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5r-7-2r=14
Subtract 2r from both sides.
3r-7=14
Combine 5r and -2r to get 3r.
3r=14+7
Add 7 to both sides.
3r=21
Add 14 and 7 to get 21.
r=\frac{21}{3}
Divide both sides by 3.
r=7
Divide 21 by 3 to get 7.
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