The graph represents function 1 and the equation represents function 2:

Question

A graph with numbers 0 to 4 on the x-axis and y-axis at increments of 1. A horizontal straight line is drawn joining the ordered pairs 0, 3 and 4, 3.

Function 2
y = 4x + 1

How much more is the rate of change of function 2 than the rate of change of function 1?

Answer 1

horizontal lines have zero slope, so rate of change (=slope)=0.
Any straight-line function has the form
y=mx+b
where m is the slope, and b is a constant.
Compare this with the equation of function 2 to determine the slope.
Since rate of change of function 1 is zero, so function 2's rate of change is m-0=m.