Solve for x (complex solution)
x=-2\sqrt{2}i\approx -0-2.828427125i
x=2\sqrt{2}i\approx 2.828427125i
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x^{2}+8+x^{2}=-8
Add x^{2} to both sides.
2x^{2}+8=-8
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}=-8-8
Subtract 8 from both sides.
2x^{2}=-16
Subtract 8 from -8 to get -16.
x^{2}=\frac{-16}{2}
Divide both sides by 2.
x^{2}=-8
Divide -16 by 2 to get -8.
x=2\sqrt{2}i x=-2\sqrt{2}i
The equation is now solved.
x^{2}+8+x^{2}=-8
Add x^{2} to both sides.
2x^{2}+8=-8
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+8+8=0
Add 8 to both sides.
2x^{2}+16=0
Add 8 and 8 to get 16.
x=\frac{0±\sqrt{0^{2}-4\times 2\times 16}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and 16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\times 16}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\times 16}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{-128}}{2\times 2}
Multiply -8 times 16.
x=\frac{0±8\sqrt{2}i}{2\times 2}
Take the square root of -128.
x=\frac{0±8\sqrt{2}i}{4}
Multiply 2 times 2.
x=2\sqrt{2}i
Now solve the equation x=\frac{0±8\sqrt{2}i}{4} when ± is plus.
x=-2\sqrt{2}i
Now solve the equation x=\frac{0±8\sqrt{2}i}{4} when ± is minus.
x=2\sqrt{2}i x=-2\sqrt{2}i
The equation is now solved.
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