Solve for x
x=-6
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\left(x-3\right)\left(3x+4\right)-3\times 2x=x\times 3\left(x-3\right)
Variable x cannot be equal to 3 since division by zero is not defined. Multiply both sides of the equation by 3\left(x-3\right), the least common multiple of 3,x-3.
3x^{2}-5x-12-3\times 2x=x\times 3\left(x-3\right)
Use the distributive property to multiply x-3 by 3x+4 and combine like terms.
3x^{2}-5x-12-6x=x\times 3\left(x-3\right)
Multiply -3 and 2 to get -6.
3x^{2}-11x-12=x\times 3\left(x-3\right)
Combine -5x and -6x to get -11x.
3x^{2}-11x-12=3x^{2}-3x\times 3
Use the distributive property to multiply x\times 3 by x-3.
3x^{2}-11x-12=3x^{2}-9x
Multiply -3 and 3 to get -9.
3x^{2}-11x-12-3x^{2}=-9x
Subtract 3x^{2} from both sides.
-11x-12=-9x
Combine 3x^{2} and -3x^{2} to get 0.
-11x-12+9x=0
Add 9x to both sides.
-2x-12=0
Combine -11x and 9x to get -2x.
-2x=12
Add 12 to both sides. Anything plus zero gives itself.
x=\frac{12}{-2}
Divide both sides by -2.
x=-6
Divide 12 by -2 to get -6.
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Simultaneous equation
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Limits
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