Solve for x (complex solution)
x=-\frac{5\sqrt{6}i}{6}\approx -0-2.041241452i
x=\frac{5\sqrt{6}i}{6}\approx 2.041241452i
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6x^{2}=-25
Subtract 25 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-\frac{25}{6}
Divide both sides by 6.
x=\frac{5\sqrt{6}i}{6} x=-\frac{5\sqrt{6}i}{6}
The equation is now solved.
6x^{2}+25=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 6\times 25}}{2\times 6}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 6 for a, 0 for b, and 25 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 6\times 25}}{2\times 6}
Square 0.
x=\frac{0±\sqrt{-24\times 25}}{2\times 6}
Multiply -4 times 6.
x=\frac{0±\sqrt{-600}}{2\times 6}
Multiply -24 times 25.
x=\frac{0±10\sqrt{6}i}{2\times 6}
Take the square root of -600.
x=\frac{0±10\sqrt{6}i}{12}
Multiply 2 times 6.
x=\frac{5\sqrt{6}i}{6}
Now solve the equation x=\frac{0±10\sqrt{6}i}{12} when ± is plus.
x=-\frac{5\sqrt{6}i}{6}
Now solve the equation x=\frac{0±10\sqrt{6}i}{12} when ± is minus.
x=\frac{5\sqrt{6}i}{6} x=-\frac{5\sqrt{6}i}{6}
The equation is now solved.
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