Solve for x (complex solution)
x=-\frac{\sqrt{105}i}{5}\approx -0-2.049390153i
x=\frac{\sqrt{105}i}{5}\approx 2.049390153i
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5x^{2}=6-27
Subtract 27 from both sides.
5x^{2}=-21
Subtract 27 from 6 to get -21.
x^{2}=-\frac{21}{5}
Divide both sides by 5.
x=\frac{\sqrt{105}i}{5} x=-\frac{\sqrt{105}i}{5}
The equation is now solved.
5x^{2}+27-6=0
Subtract 6 from both sides.
5x^{2}+21=0
Subtract 6 from 27 to get 21.
x=\frac{0±\sqrt{0^{2}-4\times 5\times 21}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and 21 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 5\times 21}}{2\times 5}
Square 0.
x=\frac{0±\sqrt{-20\times 21}}{2\times 5}
Multiply -4 times 5.
x=\frac{0±\sqrt{-420}}{2\times 5}
Multiply -20 times 21.
x=\frac{0±2\sqrt{105}i}{2\times 5}
Take the square root of -420.
x=\frac{0±2\sqrt{105}i}{10}
Multiply 2 times 5.
x=\frac{\sqrt{105}i}{5}
Now solve the equation x=\frac{0±2\sqrt{105}i}{10} when ± is plus.
x=-\frac{\sqrt{105}i}{5}
Now solve the equation x=\frac{0±2\sqrt{105}i}{10} when ± is minus.
x=\frac{\sqrt{105}i}{5} x=-\frac{\sqrt{105}i}{5}
The equation is now solved.
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