Solve for x (complex solution)
x=-\sqrt{138}i\approx -0-11.747340124i
x=\sqrt{138}i\approx 11.747340124i
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x^{2}+18+120=0
Add 10 and 8 to get 18.
x^{2}+138=0
Add 18 and 120 to get 138.
x^{2}=-138
Subtract 138 from both sides. Anything subtracted from zero gives its negation.
x=\sqrt{138}i x=-\sqrt{138}i
The equation is now solved.
x^{2}+18+120=0
Add 10 and 8 to get 18.
x^{2}+138=0
Add 18 and 120 to get 138.
x=\frac{0±\sqrt{0^{2}-4\times 138}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and 138 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 138}}{2}
Square 0.
x=\frac{0±\sqrt{-552}}{2}
Multiply -4 times 138.
x=\frac{0±2\sqrt{138}i}{2}
Take the square root of -552.
x=\sqrt{138}i
Now solve the equation x=\frac{0±2\sqrt{138}i}{2} when ± is plus.
x=-\sqrt{138}i
Now solve the equation x=\frac{0±2\sqrt{138}i}{2} when ± is minus.
x=\sqrt{138}i x=-\sqrt{138}i
The equation is now solved.
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