Solve for x
x = \frac{11}{8} = 1\frac{3}{8} = 1.375
x=0
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-\frac{5}{12}x-2-\frac{2}{3}x^{2}=-\frac{4}{3}x-2
Subtract \frac{2}{3}x^{2} from both sides.
-\frac{5}{12}x-2-\frac{2}{3}x^{2}+\frac{4}{3}x=-2
Add \frac{4}{3}x to both sides.
\frac{11}{12}x-2-\frac{2}{3}x^{2}=-2
Combine -\frac{5}{12}x and \frac{4}{3}x to get \frac{11}{12}x.
\frac{11}{12}x-2-\frac{2}{3}x^{2}+2=0
Add 2 to both sides.
\frac{11}{12}x-\frac{2}{3}x^{2}=0
Add -2 and 2 to get 0.
x\left(\frac{11}{12}-\frac{2}{3}x\right)=0
Factor out x.
x=0 x=\frac{11}{8}
To find equation solutions, solve x=0 and \frac{11}{12}-\frac{2x}{3}=0.
-\frac{5}{12}x-2-\frac{2}{3}x^{2}=-\frac{4}{3}x-2
Subtract \frac{2}{3}x^{2} from both sides.
-\frac{5}{12}x-2-\frac{2}{3}x^{2}+\frac{4}{3}x=-2
Add \frac{4}{3}x to both sides.
\frac{11}{12}x-2-\frac{2}{3}x^{2}=-2
Combine -\frac{5}{12}x and \frac{4}{3}x to get \frac{11}{12}x.
\frac{11}{12}x-2-\frac{2}{3}x^{2}+2=0
Add 2 to both sides.
\frac{11}{12}x-\frac{2}{3}x^{2}=0
Add -2 and 2 to get 0.
-\frac{2}{3}x^{2}+\frac{11}{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{11}{12}±\sqrt{\left(\frac{11}{12}\right)^{2}}}{2\left(-\frac{2}{3}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{2}{3} for a, \frac{11}{12} for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\frac{11}{12}±\frac{11}{12}}{2\left(-\frac{2}{3}\right)}
Take the square root of \left(\frac{11}{12}\right)^{2}.
x=\frac{-\frac{11}{12}±\frac{11}{12}}{-\frac{4}{3}}
Multiply 2 times -\frac{2}{3}.
x=\frac{0}{-\frac{4}{3}}
Now solve the equation x=\frac{-\frac{11}{12}±\frac{11}{12}}{-\frac{4}{3}} when ± is plus. Add -\frac{11}{12} to \frac{11}{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{11}{6}}{-\frac{4}{3}}
Now solve the equation x=\frac{-\frac{11}{12}±\frac{11}{12}}{-\frac{4}{3}} when ± is minus. Subtract \frac{11}{12} from -\frac{11}{12} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
x=\frac{11}{8}
Divide -\frac{11}{6} by -\frac{4}{3} by multiplying -\frac{11}{6} by the reciprocal of -\frac{4}{3}.
x=0 x=\frac{11}{8}
The equation is now solved.
-\frac{5}{12}x-2-\frac{2}{3}x^{2}=-\frac{4}{3}x-2
Subtract \frac{2}{3}x^{2} from both sides.
-\frac{5}{12}x-2-\frac{2}{3}x^{2}+\frac{4}{3}x=-2
Add \frac{4}{3}x to both sides.
\frac{11}{12}x-2-\frac{2}{3}x^{2}=-2
Combine -\frac{5}{12}x and \frac{4}{3}x to get \frac{11}{12}x.
\frac{11}{12}x-\frac{2}{3}x^{2}=-2+2
Add 2 to both sides.
\frac{11}{12}x-\frac{2}{3}x^{2}=0
Add -2 and 2 to get 0.
-\frac{2}{3}x^{2}+\frac{11}{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{11}{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{11}{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{11}{8}x=\frac{0}{-\frac{2}{3}}
Divide \frac{11}{12} by -\frac{2}{3} by multiplying \frac{11}{12} by the reciprocal of -\frac{2}{3}.
x^{2}-\frac{11}{8}x=0
Divide 0 by -\frac{2}{3} by multiplying 0 by the reciprocal of -\frac{2}{3}.
x^{2}-\frac{11}{8}x+\left(-\frac{11}{16}\right)^{2}=\left(-\frac{11}{16}\right)^{2}
Divide -\frac{11}{8}, the coefficient of the x term, by 2 to get -\frac{11}{16}. Then add the square of -\frac{11}{16} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{11}{8}x+\frac{121}{256}=\frac{121}{256}
Square -\frac{11}{16} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{11}{16}\right)^{2}=\frac{121}{256}
Factor x^{2}-\frac{11}{8}x+\frac{121}{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{11}{16}\right)^{2}}=\sqrt{\frac{121}{256}}
Take the square root of both sides of the equation.
x-\frac{11}{16}=\frac{11}{16} x-\frac{11}{16}=-\frac{11}{16}
Simplify.
x=\frac{11}{8} x=0
Add \frac{11}{16} to both sides of the equation.
Examples
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Linear equation
y = 3x + 4
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Matrix
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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