Solve for r
r=-8
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-16-3r=-2r+r
Combine r and -4r to get -3r.
-16-3r=-r
Combine -2r and r to get -r.
-16-3r+r=0
Add r to both sides.
-16-2r=0
Combine -3r and r to get -2r.
-2r=16
Add 16 to both sides. Anything plus zero gives itself.
r=\frac{16}{-2}
Divide both sides by -2.
r=-8
Divide 16 by -2 to get -8.
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