Adi, isnt the matrix for stretch parallel to X axis :
1 0
0 k
and that parallell to Y axis :
K 0
0 1
I remember reading it in the notes mam gave.. have you mixed them up or are u right 
m sorry...dint see ur post d last time...
By the way u must be reading it wrong or maybe u r interpreting it in d wrong way
when i say parallel to x axis...i mean...y axis invariant..nd the same goes for the next one....
so just check maybe u read it wrong....
even i m giving u right from the same notes gurl!!!!