Solve for x
x=4
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12+x\times 9=12x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
12+x\times 9-12x=0
Subtract 12x from both sides.
12-3x=0
Combine x\times 9 and -12x to get -3x.
-3x=-12
Subtract 12 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-12}{-3}
Divide both sides by -3.
x=4
Divide -12 by -3 to get 4.
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