Solve for x (complex solution)
x=-\frac{i\sqrt{30}}{5}\approx -0-1.095445115i
x=\frac{i\sqrt{30}}{5}\approx 1.095445115i
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\frac{34}{5}x^{2}=-8.16
Subtract 8.16 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-8.16\times \frac{5}{34}
Multiply both sides by \frac{5}{34}, the reciprocal of \frac{34}{5}.
x^{2}=-\frac{6}{5}
Multiply -8.16 and \frac{5}{34} to get -\frac{6}{5}.
x=\frac{\sqrt{30}i}{5} x=-\frac{\sqrt{30}i}{5}
The equation is now solved.
\frac{34}{5}x^{2}+8.16=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times \frac{34}{5}\times 8.16}}{2\times \frac{34}{5}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{34}{5} for a, 0 for b, and 8.16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{34}{5}\times 8.16}}{2\times \frac{34}{5}}
Square 0.
x=\frac{0±\sqrt{-\frac{136}{5}\times 8.16}}{2\times \frac{34}{5}}
Multiply -4 times \frac{34}{5}.
x=\frac{0±\sqrt{-\frac{27744}{125}}}{2\times \frac{34}{5}}
Multiply -\frac{136}{5} times 8.16 by multiplying numerator times numerator and denominator times denominator. Then reduce the fraction to lowest terms if possible.
x=\frac{0±\frac{68\sqrt{30}i}{25}}{2\times \frac{34}{5}}
Take the square root of -\frac{27744}{125}.
x=\frac{0±\frac{68\sqrt{30}i}{25}}{\frac{68}{5}}
Multiply 2 times \frac{34}{5}.
x=\frac{\sqrt{30}i}{5}
Now solve the equation x=\frac{0±\frac{68\sqrt{30}i}{25}}{\frac{68}{5}} when ± is plus.
x=-\frac{\sqrt{30}i}{5}
Now solve the equation x=\frac{0±\frac{68\sqrt{30}i}{25}}{\frac{68}{5}} when ± is minus.
x=\frac{\sqrt{30}i}{5} x=-\frac{\sqrt{30}i}{5}
The equation is now solved.
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