\[\boxed{\text{393.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]
\[x^{2} + \frac{9}{x^{2}} - 10 = 0\ \ \ \ \ \ \ | \cdot x^{2}\]
\[x^{4} - 10x^{2} + 9 = 0\]
\[x^{2} = t:\]
\[t^{2} - 10t + 9 = 0\]
\[D_{1} = 25 - 9 = 16\]
\[t_{1} = 5 + 4 = 9;\ \ \ \ \ \]
\[\ t_{2} = 5 - 4 = 1.\]
\[1)\ x^{2} = 9\]
\[x_{1} = 3;\ \ \ \ x_{2} = - 3;\]
\[y_{1} = \frac{3}{3} = 1;\ \ \ \ y_{2} = \frac{3}{- 3} = - 1.\]
\[2)\ x^{2} = 1\]
\[x_{1} = 1;\ \ \ \ x_{2} = - 1;\]
\[y_{1} = \frac{3}{1} = 3;\ \ \ \ y_{2} = \frac{3}{- 1} = - 3.\]
\[Ответ:(3;1);( - 3; - 1);(1;3);\]
\[( - 1;\ - 3).\]