We have to use the slope formula first
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]Let's replace the given points
[tex]m=\frac{8-3}{-8-(-4)}=\frac{5}{-8+4}=-\frac{5}{4}[/tex]Then, we use the point-slope formula to find the equation
[tex]y-y_1=m(x-x_1)[/tex]Let's replace a point and the slope,
[tex]\begin{gathered} y-3=-\frac{5}{4}(x-(-4) \\ y-3=-\frac{5}{4}(x+4) \\ y=-\frac{5}{4}x-5+3 \\ y=-\frac{5}{4}x-2 \end{gathered}[/tex]