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Solve for x (complex solution)
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2x^{2}+8=0
Add 5 and 3 to get 8.
2x^{2}=-8
Subtract 8 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-8}{2}
Divide both sides by 2.
x^{2}=-4
Divide -8 by 2 to get -4.
x=2i x=-2i
The equation is now solved.
2x^{2}+8=0
Add 5 and 3 to get 8.
x=\frac{0±\sqrt{0^{2}-4\times 2\times 8}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\times 8}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\times 8}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{-64}}{2\times 2}
Multiply -8 times 8.
x=\frac{0±8i}{2\times 2}
Take the square root of -64.
x=\frac{0±8i}{4}
Multiply 2 times 2.
x=2i
Now solve the equation x=\frac{0±8i}{4} when ± is plus.
x=-2i
Now solve the equation x=\frac{0±8i}{4} when ± is minus.
x=2i x=-2i
The equation is now solved.