For the answer to the question above,
First, we have to understand that a Y-intercept of a line is the point where a line’s graph intersects or crosses the Y-axis. In this case, we will need to look at the graph in order to find the Y-intercept. Looking at the graph I would say that the Y-intercept is (0,3.5).
For part B you can use the following:
y = m x + b
y = (7/4) * 13 + 3
26
I hope my answer helped you.