which might represent the 
- and 
-coordinates of a point on a graph that would be quite different from 
[M2.2, M2.5, P1.3, P2.2]
is: a pair of numbers or quantities written in such a way that their order is significant.
is exemplified: by the ordered pair which might represent the - and -coordinates of a point on a graph that would be quite different from [M2.2, M2.5, P1.3, P2.2]
Copyright 1997, The Open University