Solve for r
r=0
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-9r-27+11=-9\left(11r+1\right)-7
Use the distributive property to multiply -9 by r+3.
-9r-16=-9\left(11r+1\right)-7
Add -27 and 11 to get -16.
-9r-16=-99r-9-7
Use the distributive property to multiply -9 by 11r+1.
-9r-16=-99r-16
Subtract 7 from -9 to get -16.
-9r-16+99r=-16
Add 99r to both sides.
90r-16=-16
Combine -9r and 99r to get 90r.
90r=-16+16
Add 16 to both sides.
90r=0
Add -16 and 16 to get 0.
r=0
Product of two numbers is equal to 0 if at least one of them is 0. Since 90 is not equal to 0, r must be equal to 0.
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