Answer :
let us find the slope using 2 points
[tex]\begin{gathered} m=\frac{y_2-y_1}{x_2-x_1} \\ m=\frac{1-7}{-6-3} \\ m=\frac{-6}{-9} \\ m=\frac{2}{3} \end{gathered}[/tex]Therefore let us find y
[tex]\begin{gathered} \frac{2}{3}=\frac{y-1}{9+6} \\ \frac{2}{3}=\frac{y-1}{15} \\ \text{cross multiply} \\ 30=3(y-1) \\ 30=3y-3 \\ 33=3y \\ y=\frac{33}{3} \\ y=11 \end{gathered}[/tex]