Solve for x
x=-35
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x\times 12+\left(x+7\right)\times 3=\left(x+7\right)\times 18
Variable x cannot be equal to any of the values -7,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+7\right), the least common multiple of x+7,x.
x\times 12+3x+21=\left(x+7\right)\times 18
Use the distributive property to multiply x+7 by 3.
15x+21=\left(x+7\right)\times 18
Combine x\times 12 and 3x to get 15x.
15x+21=18x+126
Use the distributive property to multiply x+7 by 18.
15x+21-18x=126
Subtract 18x from both sides.
-3x+21=126
Combine 15x and -18x to get -3x.
-3x=126-21
Subtract 21 from both sides.
-3x=105
Subtract 21 from 126 to get 105.
x=\frac{105}{-3}
Divide both sides by -3.
x=-35
Divide 105 by -3 to get -35.
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