Solve for x
x = \frac{\sqrt{7} + 1}{3} \approx 1.215250437
x=\frac{1-\sqrt{7}}{3}\approx -0.54858377
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3x\times 2x+2x\left(-2\right)=4
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x.
6xx+2x\left(-2\right)=4
Multiply 3 and 2 to get 6.
6x^{2}+2x\left(-2\right)=4
Multiply x and x to get x^{2}.
6x^{2}-4x=4
Multiply 2 and -2 to get -4.
6x^{2}-4x-4=0
Subtract 4 from both sides.
x=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\times 6\left(-4\right)}}{2\times 6}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 6 for a, -4 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-4\right)±\sqrt{16-4\times 6\left(-4\right)}}{2\times 6}
Square -4.
x=\frac{-\left(-4\right)±\sqrt{16-24\left(-4\right)}}{2\times 6}
Multiply -4 times 6.
x=\frac{-\left(-4\right)±\sqrt{16+96}}{2\times 6}
Multiply -24 times -4.
x=\frac{-\left(-4\right)±\sqrt{112}}{2\times 6}
Add 16 to 96.
x=\frac{-\left(-4\right)±4\sqrt{7}}{2\times 6}
Take the square root of 112.
x=\frac{4±4\sqrt{7}}{2\times 6}
The opposite of -4 is 4.
x=\frac{4±4\sqrt{7}}{12}
Multiply 2 times 6.
x=\frac{4\sqrt{7}+4}{12}
Now solve the equation x=\frac{4±4\sqrt{7}}{12} when ± is plus. Add 4 to 4\sqrt{7}.
x=\frac{\sqrt{7}+1}{3}
Divide 4+4\sqrt{7} by 12.
x=\frac{4-4\sqrt{7}}{12}
Now solve the equation x=\frac{4±4\sqrt{7}}{12} when ± is minus. Subtract 4\sqrt{7} from 4.
x=\frac{1-\sqrt{7}}{3}
Divide 4-4\sqrt{7} by 12.
x=\frac{\sqrt{7}+1}{3} x=\frac{1-\sqrt{7}}{3}
The equation is now solved.
3x\times 2x+2x\left(-2\right)=4
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x.
6xx+2x\left(-2\right)=4
Multiply 3 and 2 to get 6.
6x^{2}+2x\left(-2\right)=4
Multiply x and x to get x^{2}.
6x^{2}-4x=4
Multiply 2 and -2 to get -4.
\frac{6x^{2}-4x}{6}=\frac{4}{6}
Divide both sides by 6.
x^{2}+\left(-\frac{4}{6}\right)x=\frac{4}{6}
Dividing by 6 undoes the multiplication by 6.
x^{2}-\frac{2}{3}x=\frac{4}{6}
Reduce the fraction \frac{-4}{6} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{2}{3}x=\frac{2}{3}
Reduce the fraction \frac{4}{6} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{2}{3}x+\left(-\frac{1}{3}\right)^{2}=\frac{2}{3}+\left(-\frac{1}{3}\right)^{2}
Divide -\frac{2}{3}, the coefficient of the x term, by 2 to get -\frac{1}{3}. Then add the square of -\frac{1}{3} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{2}{3}x+\frac{1}{9}=\frac{2}{3}+\frac{1}{9}
Square -\frac{1}{3} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{2}{3}x+\frac{1}{9}=\frac{7}{9}
Add \frac{2}{3} to \frac{1}{9} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{3}\right)^{2}=\frac{7}{9}
Factor x^{2}-\frac{2}{3}x+\frac{1}{9}. 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{1}{3}\right)^{2}}=\sqrt{\frac{7}{9}}
Take the square root of both sides of the equation.
x-\frac{1}{3}=\frac{\sqrt{7}}{3} x-\frac{1}{3}=-\frac{\sqrt{7}}{3}
Simplify.
x=\frac{\sqrt{7}+1}{3} x=\frac{1-\sqrt{7}}{3}
Add \frac{1}{3} to both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}