Solve for x
x=-1
x=12
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\left(x+3\right)\times 4x+\left(x-3\right)\left(x+3\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+3\right), the least common multiple of x-3,x+3.
\left(4x+12\right)x+\left(x-3\right)\left(x+3\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply x+3 by 4.
4x^{2}+12x+\left(x-3\right)\left(x+3\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply 4x+12 by x.
4x^{2}+12x+\left(x^{2}-9\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply x-3 by x+3 and combine like terms.
4x^{2}+12x-3x^{2}+27=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply x^{2}-9 by -3.
x^{2}+12x+27=\left(x-3\right)\left(3x-1\right)
Combine 4x^{2} and -3x^{2} to get x^{2}.
x^{2}+12x+27=3x^{2}-10x+3
Use the distributive property to multiply x-3 by 3x-1 and combine like terms.
x^{2}+12x+27-3x^{2}=-10x+3
Subtract 3x^{2} from both sides.
-2x^{2}+12x+27=-10x+3
Combine x^{2} and -3x^{2} to get -2x^{2}.
-2x^{2}+12x+27+10x=3
Add 10x to both sides.
-2x^{2}+22x+27=3
Combine 12x and 10x to get 22x.
-2x^{2}+22x+27-3=0
Subtract 3 from both sides.
-2x^{2}+22x+24=0
Subtract 3 from 27 to get 24.
x=\frac{-22±\sqrt{22^{2}-4\left(-2\right)\times 24}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 22 for b, and 24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-22±\sqrt{484-4\left(-2\right)\times 24}}{2\left(-2\right)}
Square 22.
x=\frac{-22±\sqrt{484+8\times 24}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-22±\sqrt{484+192}}{2\left(-2\right)}
Multiply 8 times 24.
x=\frac{-22±\sqrt{676}}{2\left(-2\right)}
Add 484 to 192.
x=\frac{-22±26}{2\left(-2\right)}
Take the square root of 676.
x=\frac{-22±26}{-4}
Multiply 2 times -2.
x=\frac{4}{-4}
Now solve the equation x=\frac{-22±26}{-4} when ± is plus. Add -22 to 26.
x=-1
Divide 4 by -4.
x=-\frac{48}{-4}
Now solve the equation x=\frac{-22±26}{-4} when ± is minus. Subtract 26 from -22.
x=12
Divide -48 by -4.
x=-1 x=12
The equation is now solved.
\left(x+3\right)\times 4x+\left(x-3\right)\left(x+3\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+3\right), the least common multiple of x-3,x+3.
\left(4x+12\right)x+\left(x-3\right)\left(x+3\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply x+3 by 4.
4x^{2}+12x+\left(x-3\right)\left(x+3\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply 4x+12 by x.
4x^{2}+12x+\left(x^{2}-9\right)\left(-3\right)=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply x-3 by x+3 and combine like terms.
4x^{2}+12x-3x^{2}+27=\left(x-3\right)\left(3x-1\right)
Use the distributive property to multiply x^{2}-9 by -3.
x^{2}+12x+27=\left(x-3\right)\left(3x-1\right)
Combine 4x^{2} and -3x^{2} to get x^{2}.
x^{2}+12x+27=3x^{2}-10x+3
Use the distributive property to multiply x-3 by 3x-1 and combine like terms.
x^{2}+12x+27-3x^{2}=-10x+3
Subtract 3x^{2} from both sides.
-2x^{2}+12x+27=-10x+3
Combine x^{2} and -3x^{2} to get -2x^{2}.
-2x^{2}+12x+27+10x=3
Add 10x to both sides.
-2x^{2}+22x+27=3
Combine 12x and 10x to get 22x.
-2x^{2}+22x=3-27
Subtract 27 from both sides.
-2x^{2}+22x=-24
Subtract 27 from 3 to get -24.
\frac{-2x^{2}+22x}{-2}=-\frac{24}{-2}
Divide both sides by -2.
x^{2}+\frac{22}{-2}x=-\frac{24}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-11x=-\frac{24}{-2}
Divide 22 by -2.
x^{2}-11x=12
Divide -24 by -2.
x^{2}-11x+\left(-\frac{11}{2}\right)^{2}=12+\left(-\frac{11}{2}\right)^{2}
Divide -11, the coefficient of the x term, by 2 to get -\frac{11}{2}. Then add the square of -\frac{11}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-11x+\frac{121}{4}=12+\frac{121}{4}
Square -\frac{11}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-11x+\frac{121}{4}=\frac{169}{4}
Add 12 to \frac{121}{4}.
\left(x-\frac{11}{2}\right)^{2}=\frac{169}{4}
Factor x^{2}-11x+\frac{121}{4}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{11}{2}\right)^{2}}=\sqrt{\frac{169}{4}}
Take the square root of both sides of the equation.
x-\frac{11}{2}=\frac{13}{2} x-\frac{11}{2}=-\frac{13}{2}
Simplify.
x=12 x=-1
Add \frac{11}{2} to both sides of the equation.
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