The equation of a line, knowing the slope [tex]m[/tex] and one of its points [tex](x_0,y_0)[/tex], can be retrieved using
[tex]y-y_0=m(x-x_0)[/tex]
In your case, we have
[tex]m=6,\quad (x_0,y_0)=(6,7)[/tex]
So, the equation becomes
[tex]y-7=6(x-6) \iff y=6x-29[/tex]