It is observed that the mean line of the data should pass through the points (3,3), (2,4), (1,5), (0,6), (-1,7).
Consider that the equation of a line passing through two given points is given by,
[tex]y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)[/tex]
So the equation of the best fit line passing through (3,3) and (0,6) will be,
[tex]\begin{gathered} y-3=\frac{6-3}{0-3}(x-3) \\ y-3=\frac{3}{-3}(x-3) \\ y-3=-(x-3) \\ y-3=-x+3 \\ y=-x+6 \end{gathered}[/tex]
Thus, option C is the correct choice.
