Solve for x
x=-\frac{1}{10}=-0.1
x=0
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20x^{2}+2x-0=0
Multiply 0 and 8 to get 0.
20x^{2}+2x=0
Reorder the terms.
x\left(20x+2\right)=0
Factor out x.
x=0 x=-\frac{1}{10}
To find equation solutions, solve x=0 and 20x+2=0.
20x^{2}+2x-0=0
Multiply 0 and 8 to get 0.
20x^{2}+2x=0
Reorder the terms.
x=\frac{-2±\sqrt{2^{2}}}{2\times 20}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 20 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 20}
Take the square root of 2^{2}.
x=\frac{-2±2}{40}
Multiply 2 times 20.
x=\frac{0}{40}
Now solve the equation x=\frac{-2±2}{40} when ± is plus. Add -2 to 2.
x=0
Divide 0 by 40.
x=-\frac{4}{40}
Now solve the equation x=\frac{-2±2}{40} when ± is minus. Subtract 2 from -2.
x=-\frac{1}{10}
Reduce the fraction \frac{-4}{40} to lowest terms by extracting and canceling out 4.
x=0 x=-\frac{1}{10}
The equation is now solved.
20x^{2}+2x-0=0
Multiply 0 and 8 to get 0.
20x^{2}+2x=0+0
Add 0 to both sides.
20x^{2}+2x=0
Add 0 and 0 to get 0.
\frac{20x^{2}+2x}{20}=\frac{0}{20}
Divide both sides by 20.
x^{2}+\frac{2}{20}x=\frac{0}{20}
Dividing by 20 undoes the multiplication by 20.
x^{2}+\frac{1}{10}x=\frac{0}{20}
Reduce the fraction \frac{2}{20} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{1}{10}x=0
Divide 0 by 20.
x^{2}+\frac{1}{10}x+\left(\frac{1}{20}\right)^{2}=\left(\frac{1}{20}\right)^{2}
Divide \frac{1}{10}, the coefficient of the x term, by 2 to get \frac{1}{20}. Then add the square of \frac{1}{20} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{10}x+\frac{1}{400}=\frac{1}{400}
Square \frac{1}{20} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{1}{20}\right)^{2}=\frac{1}{400}
Factor x^{2}+\frac{1}{10}x+\frac{1}{400}. 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}{20}\right)^{2}}=\sqrt{\frac{1}{400}}
Take the square root of both sides of the equation.
x+\frac{1}{20}=\frac{1}{20} x+\frac{1}{20}=-\frac{1}{20}
Simplify.
x=0 x=-\frac{1}{10}
Subtract \frac{1}{20} from both sides of the equation.
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Limits
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