\[\frac{x^{2} - 10x + 26}{3x - 5} < 0\]
\[\frac{(x - 5)^{2} + 1}{3x - 5} <\]
\[(x - 5)^{2} + 1 > 0\ \ \]
\[при\ любом\ x \in R;\]
\[3x - 5 < 0 \Longrightarrow x < 1\frac{2}{3}\ \]
\[Ответ:\left( - \infty;1\frac{2}{3} \right).\]