Solve for x
x=2\sqrt{66}-16\approx 0.248076809
x=-2\sqrt{66}-16\approx -32.248076809
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\frac{1}{32}x^{2}+x=\frac{1}{4}
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.
\frac{1}{32}x^{2}+x-\frac{1}{4}=\frac{1}{4}-\frac{1}{4}
Subtract \frac{1}{4} from both sides of the equation.
\frac{1}{32}x^{2}+x-\frac{1}{4}=0
Subtracting \frac{1}{4} from itself leaves 0.
x=\frac{-1±\sqrt{1^{2}-4\times \frac{1}{32}\left(-\frac{1}{4}\right)}}{2\times \frac{1}{32}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{32} for a, 1 for b, and -\frac{1}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\times \frac{1}{32}\left(-\frac{1}{4}\right)}}{2\times \frac{1}{32}}
Square 1.
x=\frac{-1±\sqrt{1-\frac{1}{8}\left(-\frac{1}{4}\right)}}{2\times \frac{1}{32}}
Multiply -4 times \frac{1}{32}.
x=\frac{-1±\sqrt{1+\frac{1}{32}}}{2\times \frac{1}{32}}
Multiply -\frac{1}{8} times -\frac{1}{4} by multiplying numerator times numerator and denominator times denominator. Then reduce the fraction to lowest terms if possible.
x=\frac{-1±\sqrt{\frac{33}{32}}}{2\times \frac{1}{32}}
Add 1 to \frac{1}{32}.
x=\frac{-1±\frac{\sqrt{66}}{8}}{2\times \frac{1}{32}}
Take the square root of \frac{33}{32}.
x=\frac{-1±\frac{\sqrt{66}}{8}}{\frac{1}{16}}
Multiply 2 times \frac{1}{32}.
x=\frac{\frac{\sqrt{66}}{8}-1}{\frac{1}{16}}
Now solve the equation x=\frac{-1±\frac{\sqrt{66}}{8}}{\frac{1}{16}} when ± is plus. Add -1 to \frac{\sqrt{66}}{8}.
x=2\sqrt{66}-16
Divide -1+\frac{\sqrt{66}}{8} by \frac{1}{16} by multiplying -1+\frac{\sqrt{66}}{8} by the reciprocal of \frac{1}{16}.
x=\frac{-\frac{\sqrt{66}}{8}-1}{\frac{1}{16}}
Now solve the equation x=\frac{-1±\frac{\sqrt{66}}{8}}{\frac{1}{16}} when ± is minus. Subtract \frac{\sqrt{66}}{8} from -1.
x=-2\sqrt{66}-16
Divide -1-\frac{\sqrt{66}}{8} by \frac{1}{16} by multiplying -1-\frac{\sqrt{66}}{8} by the reciprocal of \frac{1}{16}.
x=2\sqrt{66}-16 x=-2\sqrt{66}-16
The equation is now solved.
\frac{1}{32}x^{2}+x=\frac{1}{4}
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{1}{32}x^{2}+x}{\frac{1}{32}}=\frac{\frac{1}{4}}{\frac{1}{32}}
Multiply both sides by 32.
x^{2}+\frac{1}{\frac{1}{32}}x=\frac{\frac{1}{4}}{\frac{1}{32}}
Dividing by \frac{1}{32} undoes the multiplication by \frac{1}{32}.
x^{2}+32x=\frac{\frac{1}{4}}{\frac{1}{32}}
Divide 1 by \frac{1}{32} by multiplying 1 by the reciprocal of \frac{1}{32}.
x^{2}+32x=8
Divide \frac{1}{4} by \frac{1}{32} by multiplying \frac{1}{4} by the reciprocal of \frac{1}{32}.
x^{2}+32x+16^{2}=8+16^{2}
Divide 32, the coefficient of the x term, by 2 to get 16. Then add the square of 16 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+32x+256=8+256
Square 16.
x^{2}+32x+256=264
Add 8 to 256.
\left(x+16\right)^{2}=264
Factor x^{2}+32x+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+16\right)^{2}}=\sqrt{264}
Take the square root of both sides of the equation.
x+16=2\sqrt{66} x+16=-2\sqrt{66}
Simplify.
x=2\sqrt{66}-16 x=-2\sqrt{66}-16
Subtract 16 from both sides of the equation.
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Simultaneous equation
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Limits
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