Solve for x
x=16
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\left(x+12\right)\times 12=x\times 21
Variable x cannot be equal to any of the values -12,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+12\right), the least common multiple of x,x+12.
12x+144=x\times 21
Use the distributive property to multiply x+12 by 12.
12x+144-x\times 21=0
Subtract x\times 21 from both sides.
-9x+144=0
Combine 12x and -x\times 21 to get -9x.
-9x=-144
Subtract 144 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-144}{-9}
Divide both sides by -9.
x=16
Divide -144 by -9 to get 16.
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