How do you identify the important parts of #y = x^2-3x+2# to graph it?
In my class, we learned the acronym RAHTEY. It stands for Roots, Asymptotes, Holes, Tangency/Togetherness, End behavior, and Y-intercept. Here is a video that describes how to calculate and use each part of the acronym to determine the graph.
Just for your information, the video does not use the H in the acronym. Holes occur when you can factor a term out of both the numerator and denominator. To graph holes, simply draw an open circle at the location of any determined holes.