Solve for r
r=-2
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1.8r+9+5.7r=-6
Add 5.7r to both sides.
7.5r+9=-6
Combine 1.8r and 5.7r to get 7.5r.
7.5r=-6-9
Subtract 9 from both sides.
7.5r=-15
Subtract 9 from -6 to get -15.
r=\frac{-15}{7.5}
Divide both sides by 7.5.
r=\frac{-150}{75}
Expand \frac{-15}{7.5} by multiplying both numerator and the denominator by 10.
r=-2
Divide -150 by 75 to get -2.
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