Solve for x
x=12
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84-3x=4x
Multiply both sides of the equation by 12, the least common multiple of 4,3.
84-3x-4x=0
Subtract 4x from both sides.
84-7x=0
Combine -3x and -4x to get -7x.
-7x=-84
Subtract 84 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-84}{-7}
Divide both sides by -7.
x=12
Divide -84 by -7 to get 12.
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