Solve for x
x=7
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12x=6x+42
Combine 3x and 9x to get 12x.
12x-6x=42
Subtract 6x from both sides.
6x=42
Combine 12x and -6x to get 6x.
x=\frac{42}{6}
Divide both sides by 6.
x=7
Divide 42 by 6 to get 7.
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