Solve for x
x = -\frac{9}{4} = -2\frac{1}{4} = -2.25
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3\times 4-\left(3x+18\right)=x+3
Variable x cannot be equal to any of the values -6,-3 since division by zero is not defined. Multiply both sides of the equation by 3\left(x+3\right)\left(x+6\right), the least common multiple of x^{2}+9x+18,x+3,3x+18.
12-\left(3x+18\right)=x+3
Multiply 3 and 4 to get 12.
12-3x-18=x+3
To find the opposite of 3x+18, find the opposite of each term.
-6-3x=x+3
Subtract 18 from 12 to get -6.
-6-3x-x=3
Subtract x from both sides.
-6-4x=3
Combine -3x and -x to get -4x.
-4x=3+6
Add 6 to both sides.
-4x=9
Add 3 and 6 to get 9.
x=\frac{9}{-4}
Divide both sides by -4.
x=-\frac{9}{4}
Fraction \frac{9}{-4} can be rewritten as -\frac{9}{4} by extracting the negative sign.
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