Solve for r
r=-8
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1+8r=\frac{-189}{3}
Divide both sides by 3.
1+8r=-63
Divide -189 by 3 to get -63.
8r=-63-1
Subtract 1 from both sides.
8r=-64
Subtract 1 from -63 to get -64.
r=\frac{-64}{8}
Divide both sides by 8.
r=-8
Divide -64 by 8 to get -8.
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