The table represents a linear function. Which is the slope of the function?

From the table we have the points (-4, -2) and (-2, -10).
The formula of a slope:
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
Substitute:
[tex]m=\dfrac{-10-(-2)}{-2-(-4)}=\dfrac{-10+2}{-2+4}=\dfrac{-8}{2}=-4[/tex]