Equation of a line in slope-intercept form:
[tex]y=mx+b[/tex]m is the slope
b is the y-intercept
As you have the slope (m= -4) and a point (6,1) you use it in the equation above to find the y-intercept, as follow:
(6,1) x=6 y=1
m= -4
[tex]1=-4(6)+b[/tex]Solve b:
[tex]\begin{gathered} 1=-24+b \\ \\ 1+24=-24+24+b \\ 25=b \end{gathered}[/tex]Then, the equation of the given line in slope-intercept form is:[tex]y=-4x+25[/tex]