I was wondering if I could change the values on the x-axes. I want to have the value 3500 at origo and 0 at "3500" normally is, can this be done?

Hi all I have a(x) and b(x), a(x) is only interesting from x=0..5 and b(x) from 5..10. How can I define those to into one c(x)? I guess I need the piecewise function, but I don't understand anything from the help file.. Can anyone please explain it to me, thanks.