\[\sqrt{5x - 45} - \sqrt{8 - x}\]
\[\left\{ \begin{matrix} 5x - 45 \geq 0 \\ 8 - x \geq 0\ \ \ \ \\ \end{matrix} \right.\ \text{\ \ \ \ \ \ }\]
\[\left\{ \begin{matrix} 5x \geq 45 \\ x \leq 8\ \ \ \ \ \\ \end{matrix} \right.\ \text{\ \ \ \ \ \ }\]
\[\left\{ \begin{matrix} x \geq 9 \\ x \leq 8 \\ \end{matrix} \right.\ \]
\[Ответ:нет\ таких\ значений.\]