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Solve for x (complex solution)
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x^{2}-x+44=2
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+44-2=2-2
Subtract 2 from both sides of the equation.
x^{2}-x+44-2=0
Subtracting 2 from itself leaves 0.
x^{2}-x+42=0
Subtract 2 from 44.
x=\frac{-\left(-1\right)±\sqrt{1-4\times 42}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -1 for b, and 42 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1\right)±\sqrt{1-168}}{2}
Multiply -4 times 42.
x=\frac{-\left(-1\right)±\sqrt{-167}}{2}
Add 1 to -168.
x=\frac{-\left(-1\right)±\sqrt{167}i}{2}
Take the square root of -167.
x=\frac{1±\sqrt{167}i}{2}
The opposite of -1 is 1.
x=\frac{1+\sqrt{167}i}{2}
Now solve the equation x=\frac{1±\sqrt{167}i}{2} when ± is plus. Add 1 to i\sqrt{167}.
x=\frac{-\sqrt{167}i+1}{2}
Now solve the equation x=\frac{1±\sqrt{167}i}{2} when ± is minus. Subtract i\sqrt{167} from 1.
x=\frac{1+\sqrt{167}i}{2} x=\frac{-\sqrt{167}i+1}{2}
The equation is now solved.
x^{2}-x+44=2
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+44-44=2-44
Subtract 44 from both sides of the equation.
x^{2}-x=2-44
Subtracting 44 from itself leaves 0.
x^{2}-x=-42
Subtract 44 from 2.
x^{2}-x+\left(-\frac{1}{2}\right)^{2}=-42+\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}=-42+\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{167}{4}
Add -42 to \frac{1}{4}.
\left(x-\frac{1}{2}\right)^{2}=-\frac{167}{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{167}{4}}
Take the square root of both sides of the equation.
x-\frac{1}{2}=\frac{\sqrt{167}i}{2} x-\frac{1}{2}=-\frac{\sqrt{167}i}{2}
Simplify.
x=\frac{1+\sqrt{167}i}{2} x=\frac{-\sqrt{167}i+1}{2}
Add \frac{1}{2} to both sides of the equation.