Solve for x
x=3\sqrt{6}\approx 7.348469228
x=-3\sqrt{6}\approx -7.348469228
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-\frac{1}{2}x^{2}=23-50
Subtract 50 from both sides.
-\frac{1}{2}x^{2}=-27
Subtract 50 from 23 to get -27.
x^{2}=-27\left(-2\right)
Multiply both sides by -2, the reciprocal of -\frac{1}{2}.
x^{2}=54
Multiply -27 and -2 to get 54.
x=3\sqrt{6} x=-3\sqrt{6}
Take the square root of both sides of the equation.
50-\frac{1}{2}x^{2}-23=0
Subtract 23 from both sides.
27-\frac{1}{2}x^{2}=0
Subtract 23 from 50 to get 27.
-\frac{1}{2}x^{2}+27=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(-\frac{1}{2}\right)\times 27}}{2\left(-\frac{1}{2}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{1}{2} for a, 0 for b, and 27 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-\frac{1}{2}\right)\times 27}}{2\left(-\frac{1}{2}\right)}
Square 0.
x=\frac{0±\sqrt{2\times 27}}{2\left(-\frac{1}{2}\right)}
Multiply -4 times -\frac{1}{2}.
x=\frac{0±\sqrt{54}}{2\left(-\frac{1}{2}\right)}
Multiply 2 times 27.
x=\frac{0±3\sqrt{6}}{2\left(-\frac{1}{2}\right)}
Take the square root of 54.
x=\frac{0±3\sqrt{6}}{-1}
Multiply 2 times -\frac{1}{2}.
x=-3\sqrt{6}
Now solve the equation x=\frac{0±3\sqrt{6}}{-1} when ± is plus.
x=3\sqrt{6}
Now solve the equation x=\frac{0±3\sqrt{6}}{-1} when ± is minus.
x=-3\sqrt{6} x=3\sqrt{6}
The equation is now solved.
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Limits
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