Solve for x
x=16
x=-16
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4\times 192=x\times 3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
768=x\times 3x
Multiply 4 and 192 to get 768.
768=x^{2}\times 3
Multiply x and x to get x^{2}.
x^{2}\times 3=768
Swap sides so that all variable terms are on the left hand side.
x^{2}=\frac{768}{3}
Divide both sides by 3.
x^{2}=256
Divide 768 by 3 to get 256.
x=16 x=-16
Take the square root of both sides of the equation.
4\times 192=x\times 3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
768=x\times 3x
Multiply 4 and 192 to get 768.
768=x^{2}\times 3
Multiply x and x to get x^{2}.
x^{2}\times 3=768
Swap sides so that all variable terms are on the left hand side.
x^{2}\times 3-768=0
Subtract 768 from both sides.
3x^{2}-768=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times 3\left(-768\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 0 for b, and -768 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 3\left(-768\right)}}{2\times 3}
Square 0.
x=\frac{0±\sqrt{-12\left(-768\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{0±\sqrt{9216}}{2\times 3}
Multiply -12 times -768.
x=\frac{0±96}{2\times 3}
Take the square root of 9216.
x=\frac{0±96}{6}
Multiply 2 times 3.
x=16
Now solve the equation x=\frac{0±96}{6} when ± is plus. Divide 96 by 6.
x=-16
Now solve the equation x=\frac{0±96}{6} when ± is minus. Divide -96 by 6.
x=16 x=-16
The equation is now solved.
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