Solve for x
x\leq -4
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x-7-8x\geq 21
Subtract 8x from both sides.
-7x-7\geq 21
Combine x and -8x to get -7x.
-7x\geq 21+7
Add 7 to both sides.
-7x\geq 28
Add 21 and 7 to get 28.
x\leq \frac{28}{-7}
Divide both sides by -7. Since -7 is negative, the inequality direction is changed.
x\leq -4
Divide 28 by -7 to get -4.
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