The graph below represents the number of books Jaleel has read over the past x weeks.

Books Read
A graph with weeks on the x-axis and number of books on the y-axis. A line goes through points (0, 3), (1, 4), and (2, 5).

Which equation represents the graph?
y = x + 3
y = 3x
y = x – 3
y = one-third x