I don't seem to get how to graph them. Currently trying to understand how to graph: r = 3cos(2X)
When graphing polar coordinates it's important to remember that r is the length of the line, and x is the angle in radians, measured anti-clockwise from the positive "x-axis".
What I do is use values for x such as $\displaystyle 0, \frac{\pi}{8}, \frac{\pi}{4}, \frac{3\pi}{8}$ etc, and plot the r values that these give me.
When I have a good amount of points I then join them up. Remember your graphs will most likely be circles or spirals.
Also a graphic calculator is invaluable for graphing polar coordinates if you have one.