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x^{2}+x=\frac{5}{109}
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^{2}+x-\frac{5}{109}=\frac{5}{109}-\frac{5}{109}
Subtract \frac{5}{109} from both sides of the equation.
x^{2}+x-\frac{5}{109}=0
Subtracting \frac{5}{109} from itself leaves 0.
x=\frac{-1±\sqrt{1^{2}-4\left(-\frac{5}{109}\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -\frac{5}{109} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-\frac{5}{109}\right)}}{2}
Square 1.
x=\frac{-1±\sqrt{1+\frac{20}{109}}}{2}
Multiply -4 times -\frac{5}{109}.
x=\frac{-1±\sqrt{\frac{129}{109}}}{2}
Add 1 to \frac{20}{109}.
x=\frac{-1±\frac{\sqrt{14061}}{109}}{2}
Take the square root of \frac{129}{109}.
x=\frac{\frac{\sqrt{14061}}{109}-1}{2}
Now solve the equation x=\frac{-1±\frac{\sqrt{14061}}{109}}{2} when ± is plus. Add -1 to \frac{\sqrt{14061}}{109}.
x=\frac{\sqrt{14061}}{218}-\frac{1}{2}
Divide -1+\frac{\sqrt{14061}}{109} by 2.
x=\frac{-\frac{\sqrt{14061}}{109}-1}{2}
Now solve the equation x=\frac{-1±\frac{\sqrt{14061}}{109}}{2} when ± is minus. Subtract \frac{\sqrt{14061}}{109} from -1.
x=-\frac{\sqrt{14061}}{218}-\frac{1}{2}
Divide -1-\frac{\sqrt{14061}}{109} by 2.
x=\frac{\sqrt{14061}}{218}-\frac{1}{2} x=-\frac{\sqrt{14061}}{218}-\frac{1}{2}
The equation is now solved.
x^{2}+x=\frac{5}{109}
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.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=\frac{5}{109}+\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+x+\frac{1}{4}=\frac{5}{109}+\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+x+\frac{1}{4}=\frac{129}{436}
Add \frac{5}{109} to \frac{1}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{1}{2}\right)^{2}=\frac{129}{436}
Factor x^{2}+x+\frac{1}{4}. 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}{2}\right)^{2}}=\sqrt{\frac{129}{436}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{\sqrt{14061}}{218} x+\frac{1}{2}=-\frac{\sqrt{14061}}{218}
Simplify.
x=\frac{\sqrt{14061}}{218}-\frac{1}{2} x=-\frac{\sqrt{14061}}{218}-\frac{1}{2}
Subtract \frac{1}{2} from both sides of the equation.