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2+xx=x+4
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x, the least common multiple of x,2,2x.
2+x^{2}=x+4
Multiply x and x to get x^{2}.
2+x^{2}-x=4
Subtract x from both sides.
2+x^{2}-x-4=0
Subtract 4 from both sides.
-2+x^{2}-x=0
Subtract 4 from 2 to get -2.
x^{2}-x-2=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{-\left(-1\right)±\sqrt{1-4\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{-\left(-1\right)±\sqrt{1+8}}{2}
Multiply -4 times -2.
x=\frac{-\left(-1\right)±\sqrt{9}}{2}
Add 1 to 8.
x=\frac{-\left(-1\right)±3}{2}
Take the square root of 9.
x=\frac{1±3}{2}
The opposite of -1 is 1.
x=\frac{4}{2}
Now solve the equation x=\frac{1±3}{2} when ± is plus. Add 1 to 3.
x=2
Divide 4 by 2.
x=-\frac{2}{2}
Now solve the equation x=\frac{1±3}{2} when ± is minus. Subtract 3 from 1.
x=-1
Divide -2 by 2.
x=2 x=-1
The equation is now solved.
2+xx=x+4
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x, the least common multiple of x,2,2x.
2+x^{2}=x+4
Multiply x and x to get x^{2}.
2+x^{2}-x=4
Subtract x from both sides.
x^{2}-x=4-2
Subtract 2 from both sides.
x^{2}-x=2
Subtract 2 from 4 to get 2.
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=2 x=-1
Add \frac{1}{2} to both sides of the equation.