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Solve for x (complex solution)
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2x^{2}+9=0
Variable x cannot be equal to any of the values 0,6 since division by zero is not defined. Multiply both sides of the equation by x\left(x-6\right).
2x^{2}=-9
Subtract 9 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-\frac{9}{2}
Divide both sides by 2.
x=\frac{3\sqrt{2}i}{2} x=-\frac{3\sqrt{2}i}{2}
The equation is now solved.
2x^{2}+9=0
Variable x cannot be equal to any of the values 0,6 since division by zero is not defined. Multiply both sides of the equation by x\left(x-6\right).
x=\frac{0±\sqrt{0^{2}-4\times 2\times 9}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 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\times 2\times 9}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\times 9}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{-72}}{2\times 2}
Multiply -8 times 9.
x=\frac{0±6\sqrt{2}i}{2\times 2}
Take the square root of -72.
x=\frac{0±6\sqrt{2}i}{4}
Multiply 2 times 2.
x=\frac{3\sqrt{2}i}{2}
Now solve the equation x=\frac{0±6\sqrt{2}i}{4} when ± is plus.
x=-\frac{3\sqrt{2}i}{2}
Now solve the equation x=\frac{0±6\sqrt{2}i}{4} when ± is minus.
x=\frac{3\sqrt{2}i}{2} x=-\frac{3\sqrt{2}i}{2}
The equation is now solved.