the general form of the linear equation is
[tex]y=mx+b[/tex]where m is the slope and b an initial point
we have m just need find b, we can replace the slope and the point and solve b
[tex]\begin{gathered} (-7)=(-1)(4)+b \\ -7=-4+b \\ b=-7+4 \\ b=-3 \end{gathered}[/tex]so the linear equation is
[tex]y=-x-3[/tex]