The formula of a slope m:
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
We have the points (0, -1) and (5, -2). Substitute:
[tex]m=\dfrac{-2-(-1)}{5-0}=\dfrac{-2+1}{5}=-\dfrac{1}{5}[/tex]
