Solve for x (complex solution)
x=-\frac{\sqrt{195}i}{2}\approx -0-6.982120022i
x=\frac{\sqrt{195}i}{2}\approx 6.982120022i
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8x^{2}=15\left(-26\right)
Subtract 44 from 18 to get -26.
8x^{2}=-390
Multiply 15 and -26 to get -390.
x^{2}=\frac{-390}{8}
Divide both sides by 8.
x^{2}=-\frac{195}{4}
Reduce the fraction \frac{-390}{8} to lowest terms by extracting and canceling out 2.
x=\frac{\sqrt{195}i}{2} x=-\frac{\sqrt{195}i}{2}
The equation is now solved.
8x^{2}=15\left(-26\right)
Subtract 44 from 18 to get -26.
8x^{2}=-390
Multiply 15 and -26 to get -390.
8x^{2}+390=0
Add 390 to both sides.
x=\frac{0±\sqrt{0^{2}-4\times 8\times 390}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 for a, 0 for b, and 390 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 8\times 390}}{2\times 8}
Square 0.
x=\frac{0±\sqrt{-32\times 390}}{2\times 8}
Multiply -4 times 8.
x=\frac{0±\sqrt{-12480}}{2\times 8}
Multiply -32 times 390.
x=\frac{0±8\sqrt{195}i}{2\times 8}
Take the square root of -12480.
x=\frac{0±8\sqrt{195}i}{16}
Multiply 2 times 8.
x=\frac{\sqrt{195}i}{2}
Now solve the equation x=\frac{0±8\sqrt{195}i}{16} when ± is plus.
x=-\frac{\sqrt{195}i}{2}
Now solve the equation x=\frac{0±8\sqrt{195}i}{16} when ± is minus.
x=\frac{\sqrt{195}i}{2} x=-\frac{\sqrt{195}i}{2}
The equation is now solved.
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