Solve for x
x=-\frac{1}{6}\approx -0.166666667
x=0
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12x^{2}+2x=0
Multiply both sides of the equation by 3.
x\left(12x+2\right)=0
Factor out x.
x=0 x=-\frac{1}{6}
To find equation solutions, solve x=0 and 12x+2=0.
12x^{2}+2x=0
Multiply both sides of the equation by 3.
x=\frac{-2±\sqrt{2^{2}}}{2\times 12}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 12 for a, 2 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-2±2}{2\times 12}
Take the square root of 2^{2}.
x=\frac{-2±2}{24}
Multiply 2 times 12.
x=\frac{0}{24}
Now solve the equation x=\frac{-2±2}{24} when ± is plus. Add -2 to 2.
x=0
Divide 0 by 24.
x=-\frac{4}{24}
Now solve the equation x=\frac{-2±2}{24} when ± is minus. Subtract 2 from -2.
x=-\frac{1}{6}
Reduce the fraction \frac{-4}{24} to lowest terms by extracting and canceling out 4.
x=0 x=-\frac{1}{6}
The equation is now solved.
12x^{2}+2x=0
Multiply both sides of the equation by 3.
\frac{12x^{2}+2x}{12}=\frac{0}{12}
Divide both sides by 12.
x^{2}+\frac{2}{12}x=\frac{0}{12}
Dividing by 12 undoes the multiplication by 12.
x^{2}+\frac{1}{6}x=\frac{0}{12}
Reduce the fraction \frac{2}{12} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{1}{6}x=0
Divide 0 by 12.
x^{2}+\frac{1}{6}x+\left(\frac{1}{12}\right)^{2}=\left(\frac{1}{12}\right)^{2}
Divide \frac{1}{6}, the coefficient of the x term, by 2 to get \frac{1}{12}. Then add the square of \frac{1}{12} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{6}x+\frac{1}{144}=\frac{1}{144}
Square \frac{1}{12} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{1}{12}\right)^{2}=\frac{1}{144}
Factor x^{2}+\frac{1}{6}x+\frac{1}{144}. 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}{12}\right)^{2}}=\sqrt{\frac{1}{144}}
Take the square root of both sides of the equation.
x+\frac{1}{12}=\frac{1}{12} x+\frac{1}{12}=-\frac{1}{12}
Simplify.
x=0 x=-\frac{1}{6}
Subtract \frac{1}{12} from both sides of the equation.
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