The slope between two points (x1,y1) and (x2,y2) is given by:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]Plugging the values of the points given and the slope we have that:
[tex]\begin{gathered} \frac{2-8}{x-(-1)}=3 \\ \frac{-6}{x+1}=3 \\ 3(x+1)=-6 \\ x+1=-\frac{6}{3} \\ x+1=-2 \\ x=-2-1 \\ x=-3 \end{gathered}[/tex]Therefore x=-3
