\[\sqrt{\frac{y}{5} - 2} + \sqrt{3y + 6}\]
\[\left\{ \begin{matrix} \frac{y}{5} - 2 \geq 0\ \ | \cdot 5 \\ 3y + 6 \geq 0\ \ \ \ \ \ \ \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} y - 10 \geq 0 \\ 3y \geq - 6\ \ \ \ \ \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} y \geq 10\ \\ y \geq - 2 \\ \end{matrix} \right.\ \]
\[При\ y \geq 10.\]
\[Ответ:при\ y \geq 10.\]