Question 35569
Try this:
{{{(x^2-9)/(x+3)}}} The denominator will become 0 at x = -3 so we should have a discontinuity or an asymptote at this point.

Here's the graph:
{{{graph(300,200,-5,5,-10,5,((x^2-9)/(x+3)))}}}
I can't seem to get the dicontinuity to appear.