Solve for x
x = \frac{8 \sqrt{19}}{19} \approx 1.835325871
x = -\frac{8 \sqrt{19}}{19} \approx -1.835325871
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-19x^{2}+64=0
Combine x^{2} and -20x^{2} to get -19x^{2}.
-19x^{2}=-64
Subtract 64 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-64}{-19}
Divide both sides by -19.
x^{2}=\frac{64}{19}
Fraction \frac{-64}{-19} can be simplified to \frac{64}{19} by removing the negative sign from both the numerator and the denominator.
x=\frac{8\sqrt{19}}{19} x=-\frac{8\sqrt{19}}{19}
Take the square root of both sides of the equation.
-19x^{2}+64=0
Combine x^{2} and -20x^{2} to get -19x^{2}.
x=\frac{0±\sqrt{0^{2}-4\left(-19\right)\times 64}}{2\left(-19\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -19 for a, 0 for b, and 64 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-19\right)\times 64}}{2\left(-19\right)}
Square 0.
x=\frac{0±\sqrt{76\times 64}}{2\left(-19\right)}
Multiply -4 times -19.
x=\frac{0±\sqrt{4864}}{2\left(-19\right)}
Multiply 76 times 64.
x=\frac{0±16\sqrt{19}}{2\left(-19\right)}
Take the square root of 4864.
x=\frac{0±16\sqrt{19}}{-38}
Multiply 2 times -19.
x=-\frac{8\sqrt{19}}{19}
Now solve the equation x=\frac{0±16\sqrt{19}}{-38} when ± is plus.
x=\frac{8\sqrt{19}}{19}
Now solve the equation x=\frac{0±16\sqrt{19}}{-38} when ± is minus.
x=-\frac{8\sqrt{19}}{19} x=\frac{8\sqrt{19}}{19}
The equation is now solved.
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