Solve for x
x = \frac{39}{8} = 4\frac{7}{8} = 4.875
x=0
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\frac{4}{9}x^{2}-\frac{8}{3}x+5+\frac{1}{2}x=5
Add \frac{1}{2}x to both sides.
\frac{4}{9}x^{2}-\frac{13}{6}x+5=5
Combine -\frac{8}{3}x and \frac{1}{2}x to get -\frac{13}{6}x.
\frac{4}{9}x^{2}-\frac{13}{6}x+5-5=0
Subtract 5 from both sides.
\frac{4}{9}x^{2}-\frac{13}{6}x=0
Subtract 5 from 5 to get 0.
x\left(\frac{4}{9}x-\frac{13}{6}\right)=0
Factor out x.
x=0 x=\frac{39}{8}
To find equation solutions, solve x=0 and \frac{4x}{9}-\frac{13}{6}=0.
\frac{4}{9}x^{2}-\frac{8}{3}x+5+\frac{1}{2}x=5
Add \frac{1}{2}x to both sides.
\frac{4}{9}x^{2}-\frac{13}{6}x+5=5
Combine -\frac{8}{3}x and \frac{1}{2}x to get -\frac{13}{6}x.
\frac{4}{9}x^{2}-\frac{13}{6}x+5-5=0
Subtract 5 from both sides.
\frac{4}{9}x^{2}-\frac{13}{6}x=0
Subtract 5 from 5 to get 0.
x=\frac{-\left(-\frac{13}{6}\right)±\sqrt{\left(-\frac{13}{6}\right)^{2}}}{2\times \frac{4}{9}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{4}{9} for a, -\frac{13}{6} for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-\frac{13}{6}\right)±\frac{13}{6}}{2\times \frac{4}{9}}
Take the square root of \left(-\frac{13}{6}\right)^{2}.
x=\frac{\frac{13}{6}±\frac{13}{6}}{2\times \frac{4}{9}}
The opposite of -\frac{13}{6} is \frac{13}{6}.
x=\frac{\frac{13}{6}±\frac{13}{6}}{\frac{8}{9}}
Multiply 2 times \frac{4}{9}.
x=\frac{\frac{13}{3}}{\frac{8}{9}}
Now solve the equation x=\frac{\frac{13}{6}±\frac{13}{6}}{\frac{8}{9}} when ± is plus. Add \frac{13}{6} to \frac{13}{6} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=\frac{39}{8}
Divide \frac{13}{3} by \frac{8}{9} by multiplying \frac{13}{3} by the reciprocal of \frac{8}{9}.
x=\frac{0}{\frac{8}{9}}
Now solve the equation x=\frac{\frac{13}{6}±\frac{13}{6}}{\frac{8}{9}} when ± is minus. Subtract \frac{13}{6} from \frac{13}{6} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
x=0
Divide 0 by \frac{8}{9} by multiplying 0 by the reciprocal of \frac{8}{9}.
x=\frac{39}{8} x=0
The equation is now solved.
\frac{4}{9}x^{2}-\frac{8}{3}x+5+\frac{1}{2}x=5
Add \frac{1}{2}x to both sides.
\frac{4}{9}x^{2}-\frac{13}{6}x+5=5
Combine -\frac{8}{3}x and \frac{1}{2}x to get -\frac{13}{6}x.
\frac{4}{9}x^{2}-\frac{13}{6}x=5-5
Subtract 5 from both sides.
\frac{4}{9}x^{2}-\frac{13}{6}x=0
Subtract 5 from 5 to get 0.
\frac{\frac{4}{9}x^{2}-\frac{13}{6}x}{\frac{4}{9}}=\frac{0}{\frac{4}{9}}
Divide both sides of the equation by \frac{4}{9}, which is the same as multiplying both sides by the reciprocal of the fraction.
x^{2}+\left(-\frac{\frac{13}{6}}{\frac{4}{9}}\right)x=\frac{0}{\frac{4}{9}}
Dividing by \frac{4}{9} undoes the multiplication by \frac{4}{9}.
x^{2}-\frac{39}{8}x=\frac{0}{\frac{4}{9}}
Divide -\frac{13}{6} by \frac{4}{9} by multiplying -\frac{13}{6} by the reciprocal of \frac{4}{9}.
x^{2}-\frac{39}{8}x=0
Divide 0 by \frac{4}{9} by multiplying 0 by the reciprocal of \frac{4}{9}.
x^{2}-\frac{39}{8}x+\left(-\frac{39}{16}\right)^{2}=\left(-\frac{39}{16}\right)^{2}
Divide -\frac{39}{8}, the coefficient of the x term, by 2 to get -\frac{39}{16}. Then add the square of -\frac{39}{16} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{39}{8}x+\frac{1521}{256}=\frac{1521}{256}
Square -\frac{39}{16} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{39}{16}\right)^{2}=\frac{1521}{256}
Factor x^{2}-\frac{39}{8}x+\frac{1521}{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{39}{16}\right)^{2}}=\sqrt{\frac{1521}{256}}
Take the square root of both sides of the equation.
x-\frac{39}{16}=\frac{39}{16} x-\frac{39}{16}=-\frac{39}{16}
Simplify.
x=\frac{39}{8} x=0
Add \frac{39}{16} to 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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