Solve for r
r=-2
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-3r-15=3\left(r-1\right)
Use the distributive property to multiply -3 by r+5.
-3r-15=3r-3
Use the distributive property to multiply 3 by r-1.
-3r-15-3r=-3
Subtract 3r from both sides.
-6r-15=-3
Combine -3r and -3r to get -6r.
-6r=-3+15
Add 15 to both sides.
-6r=12
Add -3 and 15 to get 12.
r=\frac{12}{-6}
Divide both sides by -6.
r=-2
Divide 12 by -6 to get -2.
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