Answer
$ y=-\frac{1}{4}x-2$
Work Step by Step
Let $(x_{1},y_{1})=(-4,-1)$ and $(x_{2},y_{2})=(8,-4)$
Slope $m= \frac{y_{2}-y_{1}}{x_{2}-x_{1}}=\frac{-4-(-1)}{8-(-4)}=\frac{-3}{12}=-\frac{1}{4}$
Point-slope form is
$y-y_{1}=m(x-x_{1})$
Substituting the values, we get
$y-(-1)=-\frac{1}{4}(x-(-4))$
$\implies y+1=-\frac{1}{4}(x+4)$
$\implies y+1=-\frac{1}{4}x-1$
$\implies y=-\frac{1}{4}x-2$
The equation of line is
$ y=-\frac{1}{4}x-2$