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10x^{2}-8x=0
Subtract 8x from both sides.
x\left(10x-8\right)=0
Factor out x.
x=0 x=\frac{4}{5}
To find equation solutions, solve x=0 and 10x-8=0.
10x^{2}-8x=0
Subtract 8x from both sides.
x=\frac{-\left(-8\right)±\sqrt{\left(-8\right)^{2}}}{2\times 10}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 10 for a, -8 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-8\right)±8}{2\times 10}
Take the square root of \left(-8\right)^{2}.
x=\frac{8±8}{2\times 10}
The opposite of -8 is 8.
x=\frac{8±8}{20}
Multiply 2 times 10.
x=\frac{16}{20}
Now solve the equation x=\frac{8±8}{20} when ± is plus. Add 8 to 8.
x=\frac{4}{5}
Reduce the fraction \frac{16}{20} to lowest terms by extracting and canceling out 4.
x=\frac{0}{20}
Now solve the equation x=\frac{8±8}{20} when ± is minus. Subtract 8 from 8.
x=0
Divide 0 by 20.
x=\frac{4}{5} x=0
The equation is now solved.
10x^{2}-8x=0
Subtract 8x from both sides.
\frac{10x^{2}-8x}{10}=\frac{0}{10}
Divide both sides by 10.
x^{2}+\left(-\frac{8}{10}\right)x=\frac{0}{10}
Dividing by 10 undoes the multiplication by 10.
x^{2}-\frac{4}{5}x=\frac{0}{10}
Reduce the fraction \frac{-8}{10} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{4}{5}x=0
Divide 0 by 10.
x^{2}-\frac{4}{5}x+\left(-\frac{2}{5}\right)^{2}=\left(-\frac{2}{5}\right)^{2}
Divide -\frac{4}{5}, the coefficient of the x term, by 2 to get -\frac{2}{5}. Then add the square of -\frac{2}{5} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{4}{5}x+\frac{4}{25}=\frac{4}{25}
Square -\frac{2}{5} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{2}{5}\right)^{2}=\frac{4}{25}
Factor x^{2}-\frac{4}{5}x+\frac{4}{25}. 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{2}{5}\right)^{2}}=\sqrt{\frac{4}{25}}
Take the square root of both sides of the equation.
x-\frac{2}{5}=\frac{2}{5} x-\frac{2}{5}=-\frac{2}{5}
Simplify.
x=\frac{4}{5} x=0
Add \frac{2}{5} to both sides of the equation.