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46x^{2}-18x+3=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(-18\right)±\sqrt{\left(-18\right)^{2}-4\times 46\times 3}}{2\times 46}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 46 for a, -18 for b, and 3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-18\right)±\sqrt{324-4\times 46\times 3}}{2\times 46}
Square -18.
x=\frac{-\left(-18\right)±\sqrt{324-184\times 3}}{2\times 46}
Multiply -4 times 46.
x=\frac{-\left(-18\right)±\sqrt{324-552}}{2\times 46}
Multiply -184 times 3.
x=\frac{-\left(-18\right)±\sqrt{-228}}{2\times 46}
Add 324 to -552.
x=\frac{-\left(-18\right)±2\sqrt{57}i}{2\times 46}
Take the square root of -228.
x=\frac{18±2\sqrt{57}i}{2\times 46}
The opposite of -18 is 18.
x=\frac{18±2\sqrt{57}i}{92}
Multiply 2 times 46.
x=\frac{18+2\sqrt{57}i}{92}
Now solve the equation x=\frac{18±2\sqrt{57}i}{92} when ± is plus. Add 18 to 2i\sqrt{57}.
x=\frac{9+\sqrt{57}i}{46}
Divide 18+2i\sqrt{57} by 92.
x=\frac{-2\sqrt{57}i+18}{92}
Now solve the equation x=\frac{18±2\sqrt{57}i}{92} when ± is minus. Subtract 2i\sqrt{57} from 18.
x=\frac{-\sqrt{57}i+9}{46}
Divide 18-2i\sqrt{57} by 92.
x=\frac{9+\sqrt{57}i}{46} x=\frac{-\sqrt{57}i+9}{46}
The equation is now solved.
46x^{2}-18x+3=0
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.
46x^{2}-18x+3-3=-3
Subtract 3 from both sides of the equation.
46x^{2}-18x=-3
Subtracting 3 from itself leaves 0.
\frac{46x^{2}-18x}{46}=-\frac{3}{46}
Divide both sides by 46.
x^{2}+\left(-\frac{18}{46}\right)x=-\frac{3}{46}
Dividing by 46 undoes the multiplication by 46.
x^{2}-\frac{9}{23}x=-\frac{3}{46}
Reduce the fraction \frac{-18}{46} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{9}{23}x+\left(-\frac{9}{46}\right)^{2}=-\frac{3}{46}+\left(-\frac{9}{46}\right)^{2}
Divide -\frac{9}{23}, the coefficient of the x term, by 2 to get -\frac{9}{46}. Then add the square of -\frac{9}{46} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{9}{23}x+\frac{81}{2116}=-\frac{3}{46}+\frac{81}{2116}
Square -\frac{9}{46} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{9}{23}x+\frac{81}{2116}=-\frac{57}{2116}
Add -\frac{3}{46} to \frac{81}{2116} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{9}{46}\right)^{2}=-\frac{57}{2116}
Factor x^{2}-\frac{9}{23}x+\frac{81}{2116}. 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{9}{46}\right)^{2}}=\sqrt{-\frac{57}{2116}}
Take the square root of both sides of the equation.
x-\frac{9}{46}=\frac{\sqrt{57}i}{46} x-\frac{9}{46}=-\frac{\sqrt{57}i}{46}
Simplify.
x=\frac{9+\sqrt{57}i}{46} x=\frac{-\sqrt{57}i+9}{46}
Add \frac{9}{46} to both sides of the equation.