Explanation:
-4 is your y-intercept, that's where you should start when beginning to graph your equation.
2/3 is your slope, think rise/run, or y/x.
from -4 on the y-axis, go up the y-axis 2, then (because the slope is positive) go right 3, and plot a point there. from that point, move up 2 and right 3. once you've done that to the end of the graph, go back to the y intercept and do essentially the same thing. except now it's down 2, left 3.
hope this helps :)