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Solve for x (complex solution)
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3x^{2}+20=0
Add 19 and 1 to get 20.
3x^{2}=-20
Subtract 20 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-\frac{20}{3}
Divide both sides by 3.
x=\frac{2\sqrt{15}i}{3} x=-\frac{2\sqrt{15}i}{3}
The equation is now solved.
3x^{2}+20=0
Add 19 and 1 to get 20.
x=\frac{0±\sqrt{0^{2}-4\times 3\times 20}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 0 for b, and 20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 3\times 20}}{2\times 3}
Square 0.
x=\frac{0±\sqrt{-12\times 20}}{2\times 3}
Multiply -4 times 3.
x=\frac{0±\sqrt{-240}}{2\times 3}
Multiply -12 times 20.
x=\frac{0±4\sqrt{15}i}{2\times 3}
Take the square root of -240.
x=\frac{0±4\sqrt{15}i}{6}
Multiply 2 times 3.
x=\frac{2\sqrt{15}i}{3}
Now solve the equation x=\frac{0±4\sqrt{15}i}{6} when ± is plus.
x=-\frac{2\sqrt{15}i}{3}
Now solve the equation x=\frac{0±4\sqrt{15}i}{6} when ± is minus.
x=\frac{2\sqrt{15}i}{3} x=-\frac{2\sqrt{15}i}{3}
The equation is now solved.