Solve for x (complex solution)
x=-\frac{4\sqrt{17}i}{17}\approx -0-0.9701425i
x=\frac{4\sqrt{17}i}{17}\approx 0.9701425i
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17x^{2}=-16
Subtract 16 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-\frac{16}{17}
Divide both sides by 17.
x=\frac{4\sqrt{17}i}{17} x=-\frac{4\sqrt{17}i}{17}
The equation is now solved.
17x^{2}+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 17\times 16}}{2\times 17}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 17 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 17\times 16}}{2\times 17}
Square 0.
x=\frac{0±\sqrt{-68\times 16}}{2\times 17}
Multiply -4 times 17.
x=\frac{0±\sqrt{-1088}}{2\times 17}
Multiply -68 times 16.
x=\frac{0±8\sqrt{17}i}{2\times 17}
Take the square root of -1088.
x=\frac{0±8\sqrt{17}i}{34}
Multiply 2 times 17.
x=\frac{4\sqrt{17}i}{17}
Now solve the equation x=\frac{0±8\sqrt{17}i}{34} when ± is plus.
x=-\frac{4\sqrt{17}i}{17}
Now solve the equation x=\frac{0±8\sqrt{17}i}{34} when ± is minus.
x=\frac{4\sqrt{17}i}{17} x=-\frac{4\sqrt{17}i}{17}
The equation is now solved.
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