Solve for r
r=-8
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-\frac{1}{2}r=15-11
Subtract 11 from both sides.
-\frac{1}{2}r=4
Subtract 11 from 15 to get 4.
r=4\left(-2\right)
Multiply both sides by -2, the reciprocal of -\frac{1}{2}.
r=-8
Multiply 4 and -2 to get -8.
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