Answer:
-21
Step-by-step explanation:
If the equation of the line is
[tex]y=mx+b,[/tex]
then [tex]m[/tex] is the slope of the line and [tex]b[/tex] is the y-intercept of the line.
In your case, the equation of the line is [tex]y=5x-21.[/tex]
So, the slope of this line is [tex]m=5[/tex] and the y-intercept is [tex]b=-21.[/tex]