f(x) = abs(x-8) / x+8
how would the graph look like for this equation?
good ol' trusty Wolfram:
http://www.wolframalpha.com/input/?i=plot+f%28x%29+%3D+abs%28x-8%29+%2F+%28x%2B8%29+
vertical asymptote at x = -8, cusp at (8,0)
I suggest to make a table of values, and see why the graph is like it is.