Answer
$$0$$
Work Step by Step
Given $$\lim _{y \rightarrow-\infty}\frac{3}{y+4}$$
Then
\begin{align*}
\lim _{y \rightarrow-\infty}\frac{3}{y+4}&=\lim _{y \rightarrow-\infty}\frac{3/y}{y/y+4/y}\\
&=\lim _{y \rightarrow-\infty}\frac{3/y}{1+4/y}\\
&=\frac{0}{1+0}\\
&=0
\end{align*}