Given:
The graph represents the number of t shirts and its cost.
The objective is,
i) To find the rate of change of the graph.
ii) To explain the coordinates (0,0) and (1,9).
Explanation:
i)
The coordinates in the graph are (0,0), (1,9), (2,18), (3,27).
The general formula to find the rate of change is,
[tex]\Delta r=\frac{y_2-y_1}{x_2-x_1}[/tex]
On plugging the coordinates in the above equation,
[tex]\begin{gathered} \Delta r=\frac{9-0}{1-0}=\frac{9}{1} \\ \Delta r=\frac{18-9}{2-1}=\frac{9}{1} \\ \Delta r=\frac{27-18}{3-2}=\frac{9}{1} \end{gathered}[/tex]
Hence, the rate of change for the graph is 9.
ii)
In the graph the data in x-axis represents the number of T-shirts and the data in y-axis represents the cost of T-shirt.
So, the coordinate (0,0) represents that the cost of zero T-shirt is $0.
Similarly the coordinate (1,9) represents that the cost of one T-shirt is $9.
Hence, the cost of each T-shirt is $9.
