Final answer:
The graph of a function F(x) has a vertical asymptote at a certain value of x when the function approaches infinity or negative infinity at that value.
Step-by-step explanation:
The graph of a function F(x) has a vertical asymptote at a certain value of x when the function approaches infinity or negative infinity at that value. In other words, the graph gets infinitely close to a vertical line without actually touching it. To determine the value(s) of x where the graph has a vertical asymptote, you need to identify any values of x for which the function approaches infinity or negative infinity.