Solve for x
x\geq -\frac{21}{2}
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-4x\leq 21+21
Add 21 to both sides.
-4x\leq 42
Add 21 and 21 to get 42.
x\geq \frac{42}{-4}
Divide both sides by -4. Since -4 is negative, the inequality direction is changed.
x\geq -\frac{21}{2}
Reduce the fraction \frac{42}{-4} to lowest terms by extracting and canceling out 2.
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