jmc

The $y$-axis has equation $x=0$. Thus we need to find out what $y$ is when $x=0$. We notice that the slope of the line is $\frac{16-(-4)}{2-(-8)}=2$. So to get to $x=0$ we can start at $(2,16)$ and go left two in the $x$ direction. Since the slope of the line is $2$ we know that going left in $x$ by one results in going down in $y$ by two (i.e. $y$ will be 12). Thus the line intercepts the $y$-axis at $\boxed{(0,12)}$.