Answer
y=4
Work Step by Step
Two points clearly on the line are (0,4) and (1,4). By going from one point to the other, we see that we move up 0 units and to the right 1 unit, giving us a rise/run slope of m= $0$.
And since the line crosses the y-axis at x=4, b=4, our y-intercept.
y=mx+b
y=0(x)+4
y=4
And so our line is y=4.
