Solve for x
x=-\frac{3}{4}=-0.75
x=1
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\frac{2}{3}x^{2}-\frac{1}{6}x-\frac{1}{2}=0
Divide both sides by 6. Zero divided by any non-zero number gives zero.
x=\frac{-\left(-\frac{1}{6}\right)±\sqrt{\left(-\frac{1}{6}\right)^{2}-4\times \frac{2}{3}\left(-\frac{1}{2}\right)}}{2\times \frac{2}{3}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{2}{3} for a, -\frac{1}{6} for b, and -\frac{1}{2} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-\frac{1}{6}\right)±\sqrt{\frac{1}{36}-4\times \frac{2}{3}\left(-\frac{1}{2}\right)}}{2\times \frac{2}{3}}
Square -\frac{1}{6} by squaring both the numerator and the denominator of the fraction.
x=\frac{-\left(-\frac{1}{6}\right)±\sqrt{\frac{1}{36}-\frac{8}{3}\left(-\frac{1}{2}\right)}}{2\times \frac{2}{3}}
Multiply -4 times \frac{2}{3}.
x=\frac{-\left(-\frac{1}{6}\right)±\sqrt{\frac{1}{36}+\frac{4}{3}}}{2\times \frac{2}{3}}
Multiply -\frac{8}{3} times -\frac{1}{2} by multiplying numerator times numerator and denominator times denominator. Then reduce the fraction to lowest terms if possible.
x=\frac{-\left(-\frac{1}{6}\right)±\sqrt{\frac{49}{36}}}{2\times \frac{2}{3}}
Add \frac{1}{36} to \frac{4}{3} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=\frac{-\left(-\frac{1}{6}\right)±\frac{7}{6}}{2\times \frac{2}{3}}
Take the square root of \frac{49}{36}.
x=\frac{\frac{1}{6}±\frac{7}{6}}{2\times \frac{2}{3}}
The opposite of -\frac{1}{6} is \frac{1}{6}.
x=\frac{\frac{1}{6}±\frac{7}{6}}{\frac{4}{3}}
Multiply 2 times \frac{2}{3}.
x=\frac{\frac{4}{3}}{\frac{4}{3}}
Now solve the equation x=\frac{\frac{1}{6}±\frac{7}{6}}{\frac{4}{3}} when ± is plus. Add \frac{1}{6} to \frac{7}{6} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=1
Divide \frac{4}{3} by \frac{4}{3} by multiplying \frac{4}{3} by the reciprocal of \frac{4}{3}.
x=-\frac{1}{\frac{4}{3}}
Now solve the equation x=\frac{\frac{1}{6}±\frac{7}{6}}{\frac{4}{3}} when ± is minus. Subtract \frac{7}{6} from \frac{1}{6} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
x=-\frac{3}{4}
Divide -1 by \frac{4}{3} by multiplying -1 by the reciprocal of \frac{4}{3}.
x=1 x=-\frac{3}{4}
The equation is now solved.
\frac{2}{3}x^{2}-\frac{1}{6}x-\frac{1}{2}=0
Divide both sides by 6. Zero divided by any non-zero number gives zero.
\frac{2}{3}x^{2}-\frac{1}{6}x=\frac{1}{2}
Add \frac{1}{2} to both sides. Anything plus zero gives itself.
\frac{\frac{2}{3}x^{2}-\frac{1}{6}x}{\frac{2}{3}}=\frac{\frac{1}{2}}{\frac{2}{3}}
Divide both sides of the equation by \frac{2}{3}, which is the same as multiplying both sides by the reciprocal of the fraction.
x^{2}+\left(-\frac{\frac{1}{6}}{\frac{2}{3}}\right)x=\frac{\frac{1}{2}}{\frac{2}{3}}
Dividing by \frac{2}{3} undoes the multiplication by \frac{2}{3}.
x^{2}-\frac{1}{4}x=\frac{\frac{1}{2}}{\frac{2}{3}}
Divide -\frac{1}{6} by \frac{2}{3} by multiplying -\frac{1}{6} by the reciprocal of \frac{2}{3}.
x^{2}-\frac{1}{4}x=\frac{3}{4}
Divide \frac{1}{2} by \frac{2}{3} by multiplying \frac{1}{2} by the reciprocal of \frac{2}{3}.
x^{2}-\frac{1}{4}x+\left(-\frac{1}{8}\right)^{2}=\frac{3}{4}+\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{3}{4}+\frac{1}{64}
Square -\frac{1}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{4}x+\frac{1}{64}=\frac{49}{64}
Add \frac{3}{4} to \frac{1}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{8}\right)^{2}=\frac{49}{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{49}{64}}
Take the square root of both sides of the equation.
x-\frac{1}{8}=\frac{7}{8} x-\frac{1}{8}=-\frac{7}{8}
Simplify.
x=1 x=-\frac{3}{4}
Add \frac{1}{8} to both sides of the equation.
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