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x^{2}+3394x+3976=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{-3394±\sqrt{3394^{2}-4\times 3976}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 3394 for b, and 3976 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-3394±\sqrt{11519236-4\times 3976}}{2}
Square 3394.
x=\frac{-3394±\sqrt{11519236-15904}}{2}
Multiply -4 times 3976.
x=\frac{-3394±\sqrt{11503332}}{2}
Add 11519236 to -15904.
x=\frac{-3394±6\sqrt{319537}}{2}
Take the square root of 11503332.
x=\frac{6\sqrt{319537}-3394}{2}
Now solve the equation x=\frac{-3394±6\sqrt{319537}}{2} when ± is plus. Add -3394 to 6\sqrt{319537}.
x=3\sqrt{319537}-1697
Divide -3394+6\sqrt{319537} by 2.
x=\frac{-6\sqrt{319537}-3394}{2}
Now solve the equation x=\frac{-3394±6\sqrt{319537}}{2} when ± is minus. Subtract 6\sqrt{319537} from -3394.
x=-3\sqrt{319537}-1697
Divide -3394-6\sqrt{319537} by 2.
x=3\sqrt{319537}-1697 x=-3\sqrt{319537}-1697
The equation is now solved.
x^{2}+3394x+3976=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.
x^{2}+3394x+3976-3976=-3976
Subtract 3976 from both sides of the equation.
x^{2}+3394x=-3976
Subtracting 3976 from itself leaves 0.
x^{2}+3394x+1697^{2}=-3976+1697^{2}
Divide 3394, the coefficient of the x term, by 2 to get 1697. Then add the square of 1697 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+3394x+2879809=-3976+2879809
Square 1697.
x^{2}+3394x+2879809=2875833
Add -3976 to 2879809.
\left(x+1697\right)^{2}=2875833
Factor x^{2}+3394x+2879809. 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+1697\right)^{2}}=\sqrt{2875833}
Take the square root of both sides of the equation.
x+1697=3\sqrt{319537} x+1697=-3\sqrt{319537}
Simplify.
x=3\sqrt{319537}-1697 x=-3\sqrt{319537}-1697
Subtract 1697 from both sides of the equation.