The line in the graph is decresent, so we expect its slope to be negative. To determine its value you need to use the following formula:
[tex]m=\frac{y_1-y_2}{x_1-x_2}[/tex]
Where
m is the slope
(x₁,y₁) are the coordinates of one point of the line
(x₂,y₂) are the coordinates of a second point of the line
For the points (1,-3) and (2,-6), you can calculate the slope as:
[tex]m=\frac{-6-(-3)}{2-1}=\frac{-6+3}{1}=-3[/tex]
The slope of the line is m=-3
