Solve for r
r=9
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r+3=3r-15
Use the distributive property to multiply 3 by r-5.
r+3-3r=-15
Subtract 3r from both sides.
-2r+3=-15
Combine r and -3r to get -2r.
-2r=-15-3
Subtract 3 from both sides.
-2r=-18
Subtract 3 from -15 to get -18.
r=\frac{-18}{-2}
Divide both sides by -2.
r=9
Divide -18 by -2 to get 9.
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