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60x^{2}+12x+1=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{-12±\sqrt{12^{2}-4\times 60}}{2\times 60}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 60 for a, 12 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-12±\sqrt{144-4\times 60}}{2\times 60}
Square 12.
x=\frac{-12±\sqrt{144-240}}{2\times 60}
Multiply -4 times 60.
x=\frac{-12±\sqrt{-96}}{2\times 60}
Add 144 to -240.
x=\frac{-12±4\sqrt{6}i}{2\times 60}
Take the square root of -96.
x=\frac{-12±4\sqrt{6}i}{120}
Multiply 2 times 60.
x=\frac{-12+4\sqrt{6}i}{120}
Now solve the equation x=\frac{-12±4\sqrt{6}i}{120} when ± is plus. Add -12 to 4i\sqrt{6}.
x=\frac{\sqrt{6}i}{30}-\frac{1}{10}
Divide -12+4i\sqrt{6} by 120.
x=\frac{-4\sqrt{6}i-12}{120}
Now solve the equation x=\frac{-12±4\sqrt{6}i}{120} when ± is minus. Subtract 4i\sqrt{6} from -12.
x=-\frac{\sqrt{6}i}{30}-\frac{1}{10}
Divide -12-4i\sqrt{6} by 120.
x=\frac{\sqrt{6}i}{30}-\frac{1}{10} x=-\frac{\sqrt{6}i}{30}-\frac{1}{10}
The equation is now solved.
60x^{2}+12x+1=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.
60x^{2}+12x+1-1=-1
Subtract 1 from both sides of the equation.
60x^{2}+12x=-1
Subtracting 1 from itself leaves 0.
\frac{60x^{2}+12x}{60}=-\frac{1}{60}
Divide both sides by 60.
x^{2}+\frac{12}{60}x=-\frac{1}{60}
Dividing by 60 undoes the multiplication by 60.
x^{2}+\frac{1}{5}x=-\frac{1}{60}
Reduce the fraction \frac{12}{60} to lowest terms by extracting and canceling out 12.
x^{2}+\frac{1}{5}x+\left(\frac{1}{10}\right)^{2}=-\frac{1}{60}+\left(\frac{1}{10}\right)^{2}
Divide \frac{1}{5}, the coefficient of the x term, by 2 to get \frac{1}{10}. Then add the square of \frac{1}{10} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{5}x+\frac{1}{100}=-\frac{1}{60}+\frac{1}{100}
Square \frac{1}{10} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{1}{5}x+\frac{1}{100}=-\frac{1}{150}
Add -\frac{1}{60} to \frac{1}{100} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{1}{10}\right)^{2}=-\frac{1}{150}
Factor x^{2}+\frac{1}{5}x+\frac{1}{100}. 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}{10}\right)^{2}}=\sqrt{-\frac{1}{150}}
Take the square root of both sides of the equation.
x+\frac{1}{10}=\frac{\sqrt{6}i}{30} x+\frac{1}{10}=-\frac{\sqrt{6}i}{30}
Simplify.
x=\frac{\sqrt{6}i}{30}-\frac{1}{10} x=-\frac{\sqrt{6}i}{30}-\frac{1}{10}
Subtract \frac{1}{10} from both sides of the equation.