Solve for r
r=10
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2r+4=4r-16
Multiply both sides of the equation by 4.
2r+4-4r=-16
Subtract 4r from both sides.
-2r+4=-16
Combine 2r and -4r to get -2r.
-2r=-16-4
Subtract 4 from both sides.
-2r=-20
Subtract 4 from -16 to get -20.
r=\frac{-20}{-2}
Divide both sides by -2.
r=10
Divide -20 by -2 to get 10.
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