Solve for x
x=-9
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x+21=-4\left(-3\right)
Multiply both sides by -3, the reciprocal of -\frac{1}{3}.
x+21=12
Multiply -4 and -3 to get 12.
x=12-21
Subtract 21 from both sides.
x=-9
Subtract 21 from 12 to get -9.
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