Solve for r
r=-4
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3r-7-5r=1
Subtract 5r from both sides.
-2r-7=1
Combine 3r and -5r to get -2r.
-2r=1+7
Add 7 to both sides.
-2r=8
Add 1 and 7 to get 8.
r=\frac{8}{-2}
Divide both sides by -2.
r=-4
Divide 8 by -2 to get -4.
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