Solve for x
x = \frac{\sqrt{6}}{2} \approx 1.224744871
x = -\frac{\sqrt{6}}{2} \approx -1.224744871
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-6x^{2}+9=0
Subtract 3 from 12 to get 9.
-6x^{2}=-9
Subtract 9 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-9}{-6}
Divide both sides by -6.
x^{2}=\frac{3}{2}
Reduce the fraction \frac{-9}{-6} to lowest terms by extracting and canceling out -3.
x=\frac{\sqrt{6}}{2} x=-\frac{\sqrt{6}}{2}
Take the square root of both sides of the equation.
-6x^{2}+9=0
Subtract 3 from 12 to get 9.
x=\frac{0±\sqrt{0^{2}-4\left(-6\right)\times 9}}{2\left(-6\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -6 for a, 0 for b, and 9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-6\right)\times 9}}{2\left(-6\right)}
Square 0.
x=\frac{0±\sqrt{24\times 9}}{2\left(-6\right)}
Multiply -4 times -6.
x=\frac{0±\sqrt{216}}{2\left(-6\right)}
Multiply 24 times 9.
x=\frac{0±6\sqrt{6}}{2\left(-6\right)}
Take the square root of 216.
x=\frac{0±6\sqrt{6}}{-12}
Multiply 2 times -6.
x=-\frac{\sqrt{6}}{2}
Now solve the equation x=\frac{0±6\sqrt{6}}{-12} when ± is plus.
x=\frac{\sqrt{6}}{2}
Now solve the equation x=\frac{0±6\sqrt{6}}{-12} when ± is minus.
x=-\frac{\sqrt{6}}{2} x=\frac{\sqrt{6}}{2}
The equation is now solved.
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Limits
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