We can use the point-slope formula o find the equation of the line. The formula is the following:
[tex]y-y_0=m(x-x_0)[/tex]then, in this case we have the following:
[tex]\begin{gathered} (x_0,y_0)=(4,-2) \\ m=-2 \\ \Rightarrow y-(-2)=-2(x-4) \\ \Rightarrow y+2=-2x+8 \\ \Rightarrow y=-2x+8-2=-2x+6 \\ y=-2x+6 \end{gathered}[/tex]therefore, the equation of the line is y = -2x + 6