Solve for x
x=-2
x = \frac{7}{3} = 2\frac{1}{3} \approx 2.333333333
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3xx=x+14
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
3x^{2}=x+14
Multiply x and x to get x^{2}.
3x^{2}-x=14
Subtract x from both sides.
3x^{2}-x-14=0
Subtract 14 from both sides.
x=\frac{-\left(-1\right)±\sqrt{1-4\times 3\left(-14\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -1 for b, and -14 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1\right)±\sqrt{1-12\left(-14\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{-\left(-1\right)±\sqrt{1+168}}{2\times 3}
Multiply -12 times -14.
x=\frac{-\left(-1\right)±\sqrt{169}}{2\times 3}
Add 1 to 168.
x=\frac{-\left(-1\right)±13}{2\times 3}
Take the square root of 169.
x=\frac{1±13}{2\times 3}
The opposite of -1 is 1.
x=\frac{1±13}{6}
Multiply 2 times 3.
x=\frac{14}{6}
Now solve the equation x=\frac{1±13}{6} when ± is plus. Add 1 to 13.
x=\frac{7}{3}
Reduce the fraction \frac{14}{6} to lowest terms by extracting and canceling out 2.
x=-\frac{12}{6}
Now solve the equation x=\frac{1±13}{6} when ± is minus. Subtract 13 from 1.
x=-2
Divide -12 by 6.
x=\frac{7}{3} x=-2
The equation is now solved.
3xx=x+14
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
3x^{2}=x+14
Multiply x and x to get x^{2}.
3x^{2}-x=14
Subtract x from both sides.
\frac{3x^{2}-x}{3}=\frac{14}{3}
Divide both sides by 3.
x^{2}-\frac{1}{3}x=\frac{14}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}-\frac{1}{3}x+\left(-\frac{1}{6}\right)^{2}=\frac{14}{3}+\left(-\frac{1}{6}\right)^{2}
Divide -\frac{1}{3}, the coefficient of the x term, by 2 to get -\frac{1}{6}. Then add the square of -\frac{1}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{3}x+\frac{1}{36}=\frac{14}{3}+\frac{1}{36}
Square -\frac{1}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{3}x+\frac{1}{36}=\frac{169}{36}
Add \frac{14}{3} to \frac{1}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{6}\right)^{2}=\frac{169}{36}
Factor x^{2}-\frac{1}{3}x+\frac{1}{36}. 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}{6}\right)^{2}}=\sqrt{\frac{169}{36}}
Take the square root of both sides of the equation.
x-\frac{1}{6}=\frac{13}{6} x-\frac{1}{6}=-\frac{13}{6}
Simplify.
x=\frac{7}{3} x=-2
Add \frac{1}{6} to both sides of the equation.
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Simultaneous equation
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Differentiation
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Integration
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Limits
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