A vertical asymptote simply means that the function is undefined at a certain point. We are given that it occurs at x=25. Notice that x is in the denominator and if the denominator equals 0, the entire function is undefined. a and k are simply constants, and so they can take on any value. This is one of infinite solutions to this question:
[tex]f(x) = \frac{\pi}{x-25} + e^6[/tex]
Notice that when you plug in x=25, the denominator is 0 and the function is undefined making it a vertical asymptote.
Hope I could help!
