slope=rise/run or
if you have 2 points in (x,y) form then slope=(y₁-y₂)/(x₁-x₂)
the first point is (x₁,y₁) the second point is (x₂,y₂)
we have the points
(-1,3) and (4,-7)
x1=-1
y1=3
x2=4
y2=-7
subsitute
(3-(-7))/(-1-4)=(3+7)/(-1-4)=10/-5=2/-1=-2
slope=-2/1