Solve for x
x=\frac{\sqrt{345}-17}{2}\approx 0.787087811
x=\frac{-\sqrt{345}-17}{2}\approx -17.787087811
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-14+xx=-17x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-14+x^{2}=-17x
Multiply x and x to get x^{2}.
-14+x^{2}+17x=0
Add 17x to both sides.
x^{2}+17x-14=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{-17±\sqrt{17^{2}-4\left(-14\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 17 for b, and -14 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-17±\sqrt{289-4\left(-14\right)}}{2}
Square 17.
x=\frac{-17±\sqrt{289+56}}{2}
Multiply -4 times -14.
x=\frac{-17±\sqrt{345}}{2}
Add 289 to 56.
x=\frac{\sqrt{345}-17}{2}
Now solve the equation x=\frac{-17±\sqrt{345}}{2} when ± is plus. Add -17 to \sqrt{345}.
x=\frac{-\sqrt{345}-17}{2}
Now solve the equation x=\frac{-17±\sqrt{345}}{2} when ± is minus. Subtract \sqrt{345} from -17.
x=\frac{\sqrt{345}-17}{2} x=\frac{-\sqrt{345}-17}{2}
The equation is now solved.
-14+xx=-17x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-14+x^{2}=-17x
Multiply x and x to get x^{2}.
-14+x^{2}+17x=0
Add 17x to both sides.
x^{2}+17x=14
Add 14 to both sides. Anything plus zero gives itself.
x^{2}+17x+\left(\frac{17}{2}\right)^{2}=14+\left(\frac{17}{2}\right)^{2}
Divide 17, the coefficient of the x term, by 2 to get \frac{17}{2}. Then add the square of \frac{17}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+17x+\frac{289}{4}=14+\frac{289}{4}
Square \frac{17}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+17x+\frac{289}{4}=\frac{345}{4}
Add 14 to \frac{289}{4}.
\left(x+\frac{17}{2}\right)^{2}=\frac{345}{4}
Factor x^{2}+17x+\frac{289}{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{17}{2}\right)^{2}}=\sqrt{\frac{345}{4}}
Take the square root of both sides of the equation.
x+\frac{17}{2}=\frac{\sqrt{345}}{2} x+\frac{17}{2}=-\frac{\sqrt{345}}{2}
Simplify.
x=\frac{\sqrt{345}-17}{2} x=\frac{-\sqrt{345}-17}{2}
Subtract \frac{17}{2} from both sides of the equation.
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Limits
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