To get the that relates x and y, we choose two points on the table and use the equation of a straight line as follows:
Recall that the equation of a staight line is obtained from the formula
[tex] \frac{y-y_1}{x-x_1} = \frac{y_2-y_1}{x_2-x_1} [/tex]
Using the points (30, 18) and (36, 24), we have
[tex]\frac{y-18}{x-30} = \frac{24-18}{36-30}= \frac{6}{6} =1 \\ \\ \Rightarrow y-18=x-30 \\ \\ \Rightarrow y=x-30+18 \\ \\ \Rightarrow y=x-12[/tex]
