Hey there!!
How do we find slopes ?
Slope = [tex]\frac{y2-y1}{x2-x1}[/tex]
We are given with two co-ordinates :
(-1,8) and (3,-4)
Hence, the slope is :
[tex]\frac{-4-8}{3+1}[/tex]
... [tex]\frac{-12}{4}[/tex] = -3
The slope is -3.
Hope my answer helps!