\[(5x - 2)^{2} = \left( x^{2} - 25 \right)^{2}\]
\[5x - 2 = x^{2} - 25\]
\[x^{2} - 2x - 23 = 0\]
\[D_{1} = 1 + 23 = 24\]
\[x = 1 \pm \sqrt{24} = 1 \pm 2\sqrt{6}.\]
\[Ответ:x = 1 \pm 2\sqrt{6}.\]