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3x^{2}+x=1
Add x to both sides.
3x^{2}+x-1=0
Subtract 1 from both sides.
x=\frac{-1±\sqrt{1^{2}-4\times 3\left(-1\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 1 for b, and -1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\times 3\left(-1\right)}}{2\times 3}
Square 1.
x=\frac{-1±\sqrt{1-12\left(-1\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{-1±\sqrt{1+12}}{2\times 3}
Multiply -12 times -1.
x=\frac{-1±\sqrt{13}}{2\times 3}
Add 1 to 12.
x=\frac{-1±\sqrt{13}}{6}
Multiply 2 times 3.
x=\frac{\sqrt{13}-1}{6}
Now solve the equation x=\frac{-1±\sqrt{13}}{6} when ± is plus. Add -1 to \sqrt{13}.
x=\frac{-\sqrt{13}-1}{6}
Now solve the equation x=\frac{-1±\sqrt{13}}{6} when ± is minus. Subtract \sqrt{13} from -1.
x=\frac{\sqrt{13}-1}{6} x=\frac{-\sqrt{13}-1}{6}
The equation is now solved.
3x^{2}+x=1
Add x to both sides.
\frac{3x^{2}+x}{3}=\frac{1}{3}
Divide both sides by 3.
x^{2}+\frac{1}{3}x=\frac{1}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}+\frac{1}{3}x+\left(\frac{1}{6}\right)^{2}=\frac{1}{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{1}{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{13}{36}
Add \frac{1}{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{13}{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{13}{36}}
Take the square root of both sides of the equation.
x+\frac{1}{6}=\frac{\sqrt{13}}{6} x+\frac{1}{6}=-\frac{\sqrt{13}}{6}
Simplify.
x=\frac{\sqrt{13}-1}{6} x=\frac{-\sqrt{13}-1}{6}
Subtract \frac{1}{6} from both sides of the equation.