Solve for r
r<-4
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9r<-40+4
Add 4 to both sides.
9r<-36
Add -40 and 4 to get -36.
r<\frac{-36}{9}
Divide both sides by 9. Since 9 is positive, the inequality direction remains the same.
r<-4
Divide -36 by 9 to get -4.
Examples
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Limits
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