Solve for x
x=\sqrt{41}\approx 6.403124237
x=-\sqrt{41}\approx -6.403124237
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-x^{2}=-41
Subtract 41 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-41}{-1}
Divide both sides by -1.
x^{2}=41
Fraction \frac{-41}{-1} can be simplified to 41 by removing the negative sign from both the numerator and the denominator.
x=\sqrt{41} x=-\sqrt{41}
Take the square root of both sides of the equation.
-x^{2}+41=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 41}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and 41 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\times 41}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\times 41}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{164}}{2\left(-1\right)}
Multiply 4 times 41.
x=\frac{0±2\sqrt{41}}{2\left(-1\right)}
Take the square root of 164.
x=\frac{0±2\sqrt{41}}{-2}
Multiply 2 times -1.
x=-\sqrt{41}
Now solve the equation x=\frac{0±2\sqrt{41}}{-2} when ± is plus.
x=\sqrt{41}
Now solve the equation x=\frac{0±2\sqrt{41}}{-2} when ± is minus.
x=-\sqrt{41} x=\sqrt{41}
The equation is now solved.
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