Solve for x (complex solution)
x=-\frac{5\sqrt{15}i}{9}\approx -0-2.151657415i
x=\frac{5\sqrt{15}i}{9}\approx 2.151657415i
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3x^{2}=-\frac{125}{9}
Subtract \frac{125}{9} from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-\frac{125}{9}}{3}
Divide both sides by 3.
x^{2}=\frac{-125}{9\times 3}
Express \frac{-\frac{125}{9}}{3} as a single fraction.
x^{2}=\frac{-125}{27}
Multiply 9 and 3 to get 27.
x^{2}=-\frac{125}{27}
Fraction \frac{-125}{27} can be rewritten as -\frac{125}{27} by extracting the negative sign.
x=\frac{5\sqrt{15}i}{9} x=-\frac{5\sqrt{15}i}{9}
The equation is now solved.
3x^{2}+\frac{125}{9}=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\times 3\times \frac{125}{9}}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 0 for b, and \frac{125}{9} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 3\times \frac{125}{9}}}{2\times 3}
Square 0.
x=\frac{0±\sqrt{-12\times \frac{125}{9}}}{2\times 3}
Multiply -4 times 3.
x=\frac{0±\sqrt{-\frac{500}{3}}}{2\times 3}
Multiply -12 times \frac{125}{9}.
x=\frac{0±\frac{10\sqrt{15}i}{3}}{2\times 3}
Take the square root of -\frac{500}{3}.
x=\frac{0±\frac{10\sqrt{15}i}{3}}{6}
Multiply 2 times 3.
x=\frac{5\sqrt{15}i}{9}
Now solve the equation x=\frac{0±\frac{10\sqrt{15}i}{3}}{6} when ± is plus.
x=-\frac{5\sqrt{15}i}{9}
Now solve the equation x=\frac{0±\frac{10\sqrt{15}i}{3}}{6} when ± is minus.
x=\frac{5\sqrt{15}i}{9} x=-\frac{5\sqrt{15}i}{9}
The equation is now solved.
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