Solve for f
f<-3
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9-27f>90
Swap sides so that all variable terms are on the left hand side. This changes the sign direction.
-27f>90-9
Subtract 9 from both sides.
-27f>81
Subtract 9 from 90 to get 81.
f<\frac{81}{-27}
Divide both sides by -27. Since -27 is negative, the inequality direction is changed.
f<-3
Divide 81 by -27 to get -3.
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