Solve for x
x=-\frac{1}{8}=-0.125
x=0
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\frac{5}{12}x+2+\frac{2}{3}x^{2}=\frac{1}{3}x+2
Add \frac{2}{3}x^{2} to both sides.
\frac{5}{12}x+2+\frac{2}{3}x^{2}-\frac{1}{3}x=2
Subtract \frac{1}{3}x from both sides.
\frac{1}{12}x+2+\frac{2}{3}x^{2}=2
Combine \frac{5}{12}x and -\frac{1}{3}x to get \frac{1}{12}x.
\frac{1}{12}x+2+\frac{2}{3}x^{2}-2=0
Subtract 2 from both sides.
\frac{1}{12}x+\frac{2}{3}x^{2}=0
Subtract 2 from 2 to get 0.
x\left(\frac{1}{12}+\frac{2}{3}x\right)=0
Factor out x.
x=0 x=-\frac{1}{8}
To find equation solutions, solve x=0 and \frac{1}{12}+\frac{2x}{3}=0.
\frac{5}{12}x+2+\frac{2}{3}x^{2}=\frac{1}{3}x+2
Add \frac{2}{3}x^{2} to both sides.
\frac{5}{12}x+2+\frac{2}{3}x^{2}-\frac{1}{3}x=2
Subtract \frac{1}{3}x from both sides.
\frac{1}{12}x+2+\frac{2}{3}x^{2}=2
Combine \frac{5}{12}x and -\frac{1}{3}x to get \frac{1}{12}x.
\frac{1}{12}x+2+\frac{2}{3}x^{2}-2=0
Subtract 2 from both sides.
\frac{1}{12}x+\frac{2}{3}x^{2}=0
Subtract 2 from 2 to get 0.
\frac{2}{3}x^{2}+\frac{1}{12}x=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-\frac{1}{12}±\sqrt{\left(\frac{1}{12}\right)^{2}}}{2\times \frac{2}{3}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{2}{3} for a, \frac{1}{12} for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\frac{1}{12}±\frac{1}{12}}{2\times \frac{2}{3}}
Take the square root of \left(\frac{1}{12}\right)^{2}.
x=\frac{-\frac{1}{12}±\frac{1}{12}}{\frac{4}{3}}
Multiply 2 times \frac{2}{3}.
x=\frac{0}{\frac{4}{3}}
Now solve the equation x=\frac{-\frac{1}{12}±\frac{1}{12}}{\frac{4}{3}} when ± is plus. Add -\frac{1}{12} to \frac{1}{12} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=0
Divide 0 by \frac{4}{3} by multiplying 0 by the reciprocal of \frac{4}{3}.
x=-\frac{\frac{1}{6}}{\frac{4}{3}}
Now solve the equation x=\frac{-\frac{1}{12}±\frac{1}{12}}{\frac{4}{3}} when ± is minus. Subtract \frac{1}{12} from -\frac{1}{12} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
x=-\frac{1}{8}
Divide -\frac{1}{6} by \frac{4}{3} by multiplying -\frac{1}{6} by the reciprocal of \frac{4}{3}.
x=0 x=-\frac{1}{8}
The equation is now solved.
\frac{5}{12}x+2+\frac{2}{3}x^{2}=\frac{1}{3}x+2
Add \frac{2}{3}x^{2} to both sides.
\frac{5}{12}x+2+\frac{2}{3}x^{2}-\frac{1}{3}x=2
Subtract \frac{1}{3}x from both sides.
\frac{1}{12}x+2+\frac{2}{3}x^{2}=2
Combine \frac{5}{12}x and -\frac{1}{3}x to get \frac{1}{12}x.
\frac{1}{12}x+\frac{2}{3}x^{2}=2-2
Subtract 2 from both sides.
\frac{1}{12}x+\frac{2}{3}x^{2}=0
Subtract 2 from 2 to get 0.
\frac{2}{3}x^{2}+\frac{1}{12}x=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{\frac{2}{3}x^{2}+\frac{1}{12}x}{\frac{2}{3}}=\frac{0}{\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}+\frac{\frac{1}{12}}{\frac{2}{3}}x=\frac{0}{\frac{2}{3}}
Dividing by \frac{2}{3} undoes the multiplication by \frac{2}{3}.
x^{2}+\frac{1}{8}x=\frac{0}{\frac{2}{3}}
Divide \frac{1}{12} by \frac{2}{3} by multiplying \frac{1}{12} by the reciprocal of \frac{2}{3}.
x^{2}+\frac{1}{8}x=0
Divide 0 by \frac{2}{3} by multiplying 0 by the reciprocal of \frac{2}{3}.
x^{2}+\frac{1}{8}x+\left(\frac{1}{16}\right)^{2}=\left(\frac{1}{16}\right)^{2}
Divide \frac{1}{8}, the coefficient of the x term, by 2 to get \frac{1}{16}. Then add the square of \frac{1}{16} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{8}x+\frac{1}{256}=\frac{1}{256}
Square \frac{1}{16} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{1}{16}\right)^{2}=\frac{1}{256}
Factor x^{2}+\frac{1}{8}x+\frac{1}{256}. 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}{16}\right)^{2}}=\sqrt{\frac{1}{256}}
Take the square root of both sides of the equation.
x+\frac{1}{16}=\frac{1}{16} x+\frac{1}{16}=-\frac{1}{16}
Simplify.
x=0 x=-\frac{1}{8}
Subtract \frac{1}{16} from both sides of the equation.
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