Solve for x
x=-\frac{1}{4}=-0.25
x=0
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8x^{2}+2x=0
Add 2x to both sides.
x\left(8x+2\right)=0
Factor out x.
x=0 x=-\frac{1}{4}
To find equation solutions, solve x=0 and 8x+2=0.
8x^{2}+2x=0
Add 2x to both sides.
x=\frac{-2±\sqrt{2^{2}}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 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 8}
Take the square root of 2^{2}.
x=\frac{-2±2}{16}
Multiply 2 times 8.
x=\frac{0}{16}
Now solve the equation x=\frac{-2±2}{16} when ± is plus. Add -2 to 2.
x=0
Divide 0 by 16.
x=-\frac{4}{16}
Now solve the equation x=\frac{-2±2}{16} when ± is minus. Subtract 2 from -2.
x=-\frac{1}{4}
Reduce the fraction \frac{-4}{16} to lowest terms by extracting and canceling out 4.
x=0 x=-\frac{1}{4}
The equation is now solved.
8x^{2}+2x=0
Add 2x to both sides.
\frac{8x^{2}+2x}{8}=\frac{0}{8}
Divide both sides by 8.
x^{2}+\frac{2}{8}x=\frac{0}{8}
Dividing by 8 undoes the multiplication by 8.
x^{2}+\frac{1}{4}x=\frac{0}{8}
Reduce the fraction \frac{2}{8} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{1}{4}x=0
Divide 0 by 8.
x^{2}+\frac{1}{4}x+\left(\frac{1}{8}\right)^{2}=\left(\frac{1}{8}\right)^{2}
Divide \frac{1}{4}, the coefficient of the x term, by 2 to get \frac{1}{8}. Then add the square of \frac{1}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{4}x+\frac{1}{64}=\frac{1}{64}
Square \frac{1}{8} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{1}{8}\right)^{2}=\frac{1}{64}
Factor x^{2}+\frac{1}{4}x+\frac{1}{64}. 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}{8}\right)^{2}}=\sqrt{\frac{1}{64}}
Take the square root of both sides of the equation.
x+\frac{1}{8}=\frac{1}{8} x+\frac{1}{8}=-\frac{1}{8}
Simplify.
x=0 x=-\frac{1}{4}
Subtract \frac{1}{8} from 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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