Solve for x
x=\frac{1}{3}\approx 0.333333333
x=0
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9x^{2}-3x=0
Subtract 3x from both sides.
x\left(9x-3\right)=0
Factor out x.
x=0 x=\frac{1}{3}
To find equation solutions, solve x=0 and 9x-3=0.
9x^{2}-3x=0
Subtract 3x from both sides.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, -3 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±3}{2\times 9}
Take the square root of \left(-3\right)^{2}.
x=\frac{3±3}{2\times 9}
The opposite of -3 is 3.
x=\frac{3±3}{18}
Multiply 2 times 9.
x=\frac{6}{18}
Now solve the equation x=\frac{3±3}{18} when ± is plus. Add 3 to 3.
x=\frac{1}{3}
Reduce the fraction \frac{6}{18} to lowest terms by extracting and canceling out 6.
x=\frac{0}{18}
Now solve the equation x=\frac{3±3}{18} when ± is minus. Subtract 3 from 3.
x=0
Divide 0 by 18.
x=\frac{1}{3} x=0
The equation is now solved.
9x^{2}-3x=0
Subtract 3x from both sides.
\frac{9x^{2}-3x}{9}=\frac{0}{9}
Divide both sides by 9.
x^{2}+\left(-\frac{3}{9}\right)x=\frac{0}{9}
Dividing by 9 undoes the multiplication by 9.
x^{2}-\frac{1}{3}x=\frac{0}{9}
Reduce the fraction \frac{-3}{9} to lowest terms by extracting and canceling out 3.
x^{2}-\frac{1}{3}x=0
Divide 0 by 9.
x^{2}-\frac{1}{3}x+\left(-\frac{1}{6}\right)^{2}=\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{1}{36}
Square -\frac{1}{6} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{1}{6}\right)^{2}=\frac{1}{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{1}{36}}
Take the square root of both sides of the equation.
x-\frac{1}{6}=\frac{1}{6} x-\frac{1}{6}=-\frac{1}{6}
Simplify.
x=\frac{1}{3} x=0
Add \frac{1}{6} to both sides of the equation.
Examples
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y = 3x + 4
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Matrix
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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
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