Solve for x
x=4
x=-4
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3xx=\left(x-2\right)\left(4x+8\right)
Variable x cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by 3x\left(x-2\right), the least common multiple of x-2,3x.
3x^{2}=\left(x-2\right)\left(4x+8\right)
Multiply x and x to get x^{2}.
3x^{2}=4x^{2}-16
Use the distributive property to multiply x-2 by 4x+8 and combine like terms.
3x^{2}-4x^{2}=-16
Subtract 4x^{2} from both sides.
-x^{2}=-16
Combine 3x^{2} and -4x^{2} to get -x^{2}.
x^{2}=\frac{-16}{-1}
Divide both sides by -1.
x^{2}=16
Fraction \frac{-16}{-1} can be simplified to 16 by removing the negative sign from both the numerator and the denominator.
x=4 x=-4
Take the square root of both sides of the equation.
3xx=\left(x-2\right)\left(4x+8\right)
Variable x cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by 3x\left(x-2\right), the least common multiple of x-2,3x.
3x^{2}=\left(x-2\right)\left(4x+8\right)
Multiply x and x to get x^{2}.
3x^{2}=4x^{2}-16
Use the distributive property to multiply x-2 by 4x+8 and combine like terms.
3x^{2}-4x^{2}=-16
Subtract 4x^{2} from both sides.
-x^{2}=-16
Combine 3x^{2} and -4x^{2} to get -x^{2}.
-x^{2}+16=0
Add 16 to both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 16}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and 16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\times 16}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\times 16}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{64}}{2\left(-1\right)}
Multiply 4 times 16.
x=\frac{0±8}{2\left(-1\right)}
Take the square root of 64.
x=\frac{0±8}{-2}
Multiply 2 times -1.
x=-4
Now solve the equation x=\frac{0±8}{-2} when ± is plus. Divide 8 by -2.
x=4
Now solve the equation x=\frac{0±8}{-2} when ± is minus. Divide -8 by -2.
x=-4 x=4
The equation is now solved.
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