The slope can be calculated using the following equation:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]
Where (x1, y1) and (x2, y2) are two points on the line.
We know that if you buy 6 cans, x = 6, it will cost $3.00, y = 3.
We also know that if we buy zero cans, x = 0, it will cost nothing, y = 0.
So we have the points (0, 0) and (6, 3), so:
[tex]m=\frac{3-0}{6-0}=\frac{3}{6}=\frac{1}{2}[/tex]
So, the slope is 1/2, fourth alternative.
