Checking of lines between 2 pairs of co-oridantes corsses

[Jojoba86]

Is there a way in Excel that I can check if a pair of co-ordinates would
create a line that would cross another line between a pair of co-ordinates
(I'd have a big array of sets of co-ordinates).

For example (0,0) (1,1) would cross the line (1,0) (0,1), is there a way I
can check this in Excel?

I hope I've made myself clear, a little tricky to explain,
TIA,
Ian.