Answer:
Ok, so first, at the end of the equation, It says "+ 4" , right? So you put a point on positive 4 on the y-axis (the one that goes up and don, the vertical line.). Then, 2x means that's your slope, but since your graph only goes up to five, you gotta count down ward. So, go down from your point on the y-axis (4) twice and over to the LEFT (<--) once. Plot your point where you end up. then use a straightedge like a ruler, and connect your two points on the graph, and you have your line!
Hope this helps!