\[\sqrt{7x - 8} + \sqrt{3x - 14}\]
\[\left\{ \begin{matrix} 7x - 8 \geq 0\ \ \\ 3x - 14 \geq 0 \\ \end{matrix}\text{\ \ } \right.\ \text{\ \ \ \ }\]
\[\left\{ \begin{matrix} 7x \geq 8\ \ \\ 3x \geq 14 \\ \end{matrix}\text{\ \ } \right.\ \text{\ \ \ \ \ }\]
\[\left\{ \begin{matrix} x \geq \frac{8}{7}\text{\ \ \ } \\ x \geq \frac{14}{3} \\ \end{matrix}\text{\ \ \ \ } \right.\ \text{\ \ \ \ \ }\]
\[\left\{ \begin{matrix} x \geq 1\frac{1}{7} \\ x \geq 4\frac{2}{3} \\ \end{matrix} \right.\ \]
\[Ответ:\left\lbrack 4\frac{2}{3};\ + \infty \right).\]