We have the coordinates of two points on the line, those are (-6,-8) and (-3,-6).
Using these two points we can find the slope of the line using the following equation:
[tex]m=\frac{-8-(-6)}{-6-(-3)}=\frac{-2}{-3}=\frac{2}{3}[/tex]Use one of these points and the slope in the point slope formula to find the linear function:
[tex]\begin{gathered} y-(-6)=\frac{2}{3}(x-(-3)) \\ y+6=\frac{2}{3}(x+3) \\ y+6=\frac{2}{3}x+2 \\ y=\frac{2}{3}x+2-6 \\ y=\frac{2}{3}x-4 \end{gathered}[/tex]It means that the linear function is:
[tex]f(x)=\frac{2}{3}x-4[/tex]