Solve for x
x=-2
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2=x\left(x-1\right)+x\times 2
Variable x cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by x\left(x-1\right), the least common multiple of x\left(x-1\right),x-1.
2=x^{2}-x+x\times 2
Use the distributive property to multiply x by x-1.
2=x^{2}+x
Combine -x and x\times 2 to get x.
x^{2}+x=2
Swap sides so that all variable terms are on the left hand side.
x^{2}+x-2=0
Subtract 2 from both sides.
x=\frac{-1±\sqrt{1^{2}-4\left(-2\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-2\right)}}{2}
Square 1.
x=\frac{-1±\sqrt{1+8}}{2}
Multiply -4 times -2.
x=\frac{-1±\sqrt{9}}{2}
Add 1 to 8.
x=\frac{-1±3}{2}
Take the square root of 9.
x=\frac{2}{2}
Now solve the equation x=\frac{-1±3}{2} when ± is plus. Add -1 to 3.
x=1
Divide 2 by 2.
x=-\frac{4}{2}
Now solve the equation x=\frac{-1±3}{2} when ± is minus. Subtract 3 from -1.
x=-2
Divide -4 by 2.
x=1 x=-2
The equation is now solved.
x=-2
Variable x cannot be equal to 1.
2=x\left(x-1\right)+x\times 2
Variable x cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by x\left(x-1\right), the least common multiple of x\left(x-1\right),x-1.
2=x^{2}-x+x\times 2
Use the distributive property to multiply x by x-1.
2=x^{2}+x
Combine -x and x\times 2 to get x.
x^{2}+x=2
Swap sides so that all variable terms are on the left hand side.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=2+\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}=2+\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{9}{4}
Add 2 to \frac{1}{4}.
\left(x+\frac{1}{2}\right)^{2}=\frac{9}{4}
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{9}{4}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{3}{2} x+\frac{1}{2}=-\frac{3}{2}
Simplify.
x=1 x=-2
Subtract \frac{1}{2} from both sides of the equation.
x=-2
Variable x cannot be equal to 1.
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