Solve for x
x = -\frac{9}{2} = -4\frac{1}{2} = -4.5
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21-6\left(3-x\right)=8x+12
Multiply both sides of the equation by 12, the least common multiple of 4,2,3.
21-18+6x=8x+12
Use the distributive property to multiply -6 by 3-x.
3+6x=8x+12
Subtract 18 from 21 to get 3.
3+6x-8x=12
Subtract 8x from both sides.
3-2x=12
Combine 6x and -8x to get -2x.
-2x=12-3
Subtract 3 from both sides.
-2x=9
Subtract 3 from 12 to get 9.
x=\frac{9}{-2}
Divide both sides by -2.
x=-\frac{9}{2}
Fraction \frac{9}{-2} can be rewritten as -\frac{9}{2} by extracting the negative sign.
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