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x^{2}-3x-\left(-1\right)=3x
Subtract -1 from both sides.
x^{2}-3x+1=3x
The opposite of -1 is 1.
x^{2}-3x+1-3x=0
Subtract 3x from both sides.
x^{2}-6x+1=0
Combine -3x and -3x to get -6x.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -6 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4}}{2}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{32}}{2}
Add 36 to -4.
x=\frac{-\left(-6\right)±4\sqrt{2}}{2}
Take the square root of 32.
x=\frac{6±4\sqrt{2}}{2}
The opposite of -6 is 6.
x=\frac{4\sqrt{2}+6}{2}
Now solve the equation x=\frac{6±4\sqrt{2}}{2} when ± is plus. Add 6 to 4\sqrt{2}.
x=2\sqrt{2}+3
Divide 6+4\sqrt{2} by 2.
x=\frac{6-4\sqrt{2}}{2}
Now solve the equation x=\frac{6±4\sqrt{2}}{2} when ± is minus. Subtract 4\sqrt{2} from 6.
x=3-2\sqrt{2}
Divide 6-4\sqrt{2} by 2.
x=2\sqrt{2}+3 x=3-2\sqrt{2}
The equation is now solved.
x^{2}-3x-3x=-1
Subtract 3x from both sides.
x^{2}-6x=-1
Combine -3x and -3x to get -6x.
x^{2}-6x+\left(-3\right)^{2}=-1+\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-6x+9=-1+9
Square -3.
x^{2}-6x+9=8
Add -1 to 9.
\left(x-3\right)^{2}=8
Factor x^{2}-6x+9. 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-3\right)^{2}}=\sqrt{8}
Take the square root of both sides of the equation.
x-3=2\sqrt{2} x-3=-2\sqrt{2}
Simplify.
x=2\sqrt{2}+3 x=3-2\sqrt{2}
Add 3 to both sides of the equation.