Solve for x
x = \frac{\sqrt{481} - 1}{6} \approx 3.4886187
x=\frac{-\sqrt{481}-1}{6}\approx -3.821952033
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\frac{x}{4}+\frac{9}{4}xx-\frac{\frac{3}{4}x}{\frac{1}{6}}x+30=x
Divide \frac{3}{4}x by \frac{1}{3} to get \frac{9}{4}x.
\frac{x}{4}+\frac{9}{4}x^{2}-\frac{\frac{3}{4}x}{\frac{1}{6}}x+30=x
Multiply x and x to get x^{2}.
\frac{x}{4}+\frac{9}{4}x^{2}-\frac{9}{2}xx+30=x
Divide \frac{3}{4}x by \frac{1}{6} to get \frac{9}{2}x.
\frac{x}{4}+\frac{9}{4}x^{2}-\frac{9}{2}x^{2}+30=x
Multiply x and x to get x^{2}.
\frac{x}{4}-\frac{9}{4}x^{2}+30=x
Combine \frac{9}{4}x^{2} and -\frac{9}{2}x^{2} to get -\frac{9}{4}x^{2}.
\frac{x}{4}-\frac{9}{4}x^{2}+30-x=0
Subtract x from both sides.
-\frac{3}{4}x-\frac{9}{4}x^{2}+30=0
Combine \frac{x}{4} and -x to get -\frac{3}{4}x.
-\frac{9}{4}x^{2}-\frac{3}{4}x+30=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{-\left(-\frac{3}{4}\right)±\sqrt{\left(-\frac{3}{4}\right)^{2}-4\left(-\frac{9}{4}\right)\times 30}}{2\left(-\frac{9}{4}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{9}{4} for a, -\frac{3}{4} for b, and 30 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-\frac{3}{4}\right)±\sqrt{\frac{9}{16}-4\left(-\frac{9}{4}\right)\times 30}}{2\left(-\frac{9}{4}\right)}
Square -\frac{3}{4} by squaring both the numerator and the denominator of the fraction.
x=\frac{-\left(-\frac{3}{4}\right)±\sqrt{\frac{9}{16}+9\times 30}}{2\left(-\frac{9}{4}\right)}
Multiply -4 times -\frac{9}{4}.
x=\frac{-\left(-\frac{3}{4}\right)±\sqrt{\frac{9}{16}+270}}{2\left(-\frac{9}{4}\right)}
Multiply 9 times 30.
x=\frac{-\left(-\frac{3}{4}\right)±\sqrt{\frac{4329}{16}}}{2\left(-\frac{9}{4}\right)}
Add \frac{9}{16} to 270.
x=\frac{-\left(-\frac{3}{4}\right)±\frac{3\sqrt{481}}{4}}{2\left(-\frac{9}{4}\right)}
Take the square root of \frac{4329}{16}.
x=\frac{\frac{3}{4}±\frac{3\sqrt{481}}{4}}{2\left(-\frac{9}{4}\right)}
The opposite of -\frac{3}{4} is \frac{3}{4}.
x=\frac{\frac{3}{4}±\frac{3\sqrt{481}}{4}}{-\frac{9}{2}}
Multiply 2 times -\frac{9}{4}.
x=\frac{3\sqrt{481}+3}{-\frac{9}{2}\times 4}
Now solve the equation x=\frac{\frac{3}{4}±\frac{3\sqrt{481}}{4}}{-\frac{9}{2}} when ± is plus. Add \frac{3}{4} to \frac{3\sqrt{481}}{4}.
x=\frac{-\sqrt{481}-1}{6}
Divide \frac{3+3\sqrt{481}}{4} by -\frac{9}{2} by multiplying \frac{3+3\sqrt{481}}{4} by the reciprocal of -\frac{9}{2}.
x=\frac{3-3\sqrt{481}}{-\frac{9}{2}\times 4}
Now solve the equation x=\frac{\frac{3}{4}±\frac{3\sqrt{481}}{4}}{-\frac{9}{2}} when ± is minus. Subtract \frac{3\sqrt{481}}{4} from \frac{3}{4}.
x=\frac{\sqrt{481}-1}{6}
Divide \frac{3-3\sqrt{481}}{4} by -\frac{9}{2} by multiplying \frac{3-3\sqrt{481}}{4} by the reciprocal of -\frac{9}{2}.
x=\frac{-\sqrt{481}-1}{6} x=\frac{\sqrt{481}-1}{6}
The equation is now solved.
\frac{x}{4}+\frac{9}{4}xx-\frac{\frac{3}{4}x}{\frac{1}{6}}x+30=x
Divide \frac{3}{4}x by \frac{1}{3} to get \frac{9}{4}x.
\frac{x}{4}+\frac{9}{4}x^{2}-\frac{\frac{3}{4}x}{\frac{1}{6}}x+30=x
Multiply x and x to get x^{2}.
\frac{x}{4}+\frac{9}{4}x^{2}-\frac{9}{2}xx+30=x
Divide \frac{3}{4}x by \frac{1}{6} to get \frac{9}{2}x.
\frac{x}{4}+\frac{9}{4}x^{2}-\frac{9}{2}x^{2}+30=x
Multiply x and x to get x^{2}.
\frac{x}{4}-\frac{9}{4}x^{2}+30=x
Combine \frac{9}{4}x^{2} and -\frac{9}{2}x^{2} to get -\frac{9}{4}x^{2}.
\frac{x}{4}-\frac{9}{4}x^{2}+30-x=0
Subtract x from both sides.
-\frac{3}{4}x-\frac{9}{4}x^{2}+30=0
Combine \frac{x}{4} and -x to get -\frac{3}{4}x.
-\frac{3}{4}x-\frac{9}{4}x^{2}=-30
Subtract 30 from both sides. Anything subtracted from zero gives its negation.
-\frac{9}{4}x^{2}-\frac{3}{4}x=-30
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{9}{4}x^{2}-\frac{3}{4}x}{-\frac{9}{4}}=-\frac{30}{-\frac{9}{4}}
Divide both sides of the equation by -\frac{9}{4}, which is the same as multiplying both sides by the reciprocal of the fraction.
x^{2}+\left(-\frac{\frac{3}{4}}{-\frac{9}{4}}\right)x=-\frac{30}{-\frac{9}{4}}
Dividing by -\frac{9}{4} undoes the multiplication by -\frac{9}{4}.
x^{2}+\frac{1}{3}x=-\frac{30}{-\frac{9}{4}}
Divide -\frac{3}{4} by -\frac{9}{4} by multiplying -\frac{3}{4} by the reciprocal of -\frac{9}{4}.
x^{2}+\frac{1}{3}x=\frac{40}{3}
Divide -30 by -\frac{9}{4} by multiplying -30 by the reciprocal of -\frac{9}{4}.
x^{2}+\frac{1}{3}x+\left(\frac{1}{6}\right)^{2}=\frac{40}{3}+\left(\frac{1}{6}\right)^{2}
Divide \frac{1}{3}, the coefficient of the x term, by 2 to get \frac{1}{6}. Then add the square of \frac{1}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{3}x+\frac{1}{36}=\frac{40}{3}+\frac{1}{36}
Square \frac{1}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{1}{3}x+\frac{1}{36}=\frac{481}{36}
Add \frac{40}{3} to \frac{1}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{1}{6}\right)^{2}=\frac{481}{36}
Factor x^{2}+\frac{1}{3}x+\frac{1}{36}. 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}{6}\right)^{2}}=\sqrt{\frac{481}{36}}
Take the square root of both sides of the equation.
x+\frac{1}{6}=\frac{\sqrt{481}}{6} x+\frac{1}{6}=-\frac{\sqrt{481}}{6}
Simplify.
x=\frac{\sqrt{481}-1}{6} x=\frac{-\sqrt{481}-1}{6}
Subtract \frac{1}{6} from both sides of the equation.
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