\[y = \sqrt{x + 4} + \sqrt{2x + 3}\]
\[\left\{ \begin{matrix} x + 4 \geq 0\ \ \\ 2x + 3 \geq 0 \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x \geq - 4\ \ \\ 2x \geq - 3 \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x \geq - 4\ \ \ \\ x \geq - 1,5 \\ \end{matrix} \right.\ \]
\[x \geq - 1,5.\]