Solve for x (complex solution)
x=-\frac{\sqrt{39}i}{5}\approx -0-1.2489996i
x=\frac{\sqrt{39}i}{5}\approx 1.2489996i
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25x^{2}+39=0
Add 30 and 9 to get 39.
25x^{2}=-39
Subtract 39 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-\frac{39}{25}
Divide both sides by 25.
x=\frac{\sqrt{39}i}{5} x=-\frac{\sqrt{39}i}{5}
The equation is now solved.
25x^{2}+39=0
Add 30 and 9 to get 39.
x=\frac{0±\sqrt{0^{2}-4\times 25\times 39}}{2\times 25}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 25 for a, 0 for b, and 39 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 25\times 39}}{2\times 25}
Square 0.
x=\frac{0±\sqrt{-100\times 39}}{2\times 25}
Multiply -4 times 25.
x=\frac{0±\sqrt{-3900}}{2\times 25}
Multiply -100 times 39.
x=\frac{0±10\sqrt{39}i}{2\times 25}
Take the square root of -3900.
x=\frac{0±10\sqrt{39}i}{50}
Multiply 2 times 25.
x=\frac{\sqrt{39}i}{5}
Now solve the equation x=\frac{0±10\sqrt{39}i}{50} when ± is plus.
x=-\frac{\sqrt{39}i}{5}
Now solve the equation x=\frac{0±10\sqrt{39}i}{50} when ± is minus.
x=\frac{\sqrt{39}i}{5} x=-\frac{\sqrt{39}i}{5}
The equation is now solved.
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