Taking two of the exact points:
[tex]\begin{gathered} (x1,y1)=(2,50) \\ (x2,y2)=(6,80) \\ m=\frac{y2-y1}{x2-x1}=\frac{80-50}{6-2}=\frac{30}{4}=7.5 \\ \end{gathered}[/tex]
From the graph we can also conclude that the y-intercept could be 45, therefore the function which best models that data is:
[tex]y=6.52x+45[/tex]
