Question

can somebody tell me how to find transition matrix

Answer 1

If you know what happens due to the transformation you can figure it out.
If it reflecting across the x-axis, the x-values stay the same and the y-values become opposite...
[1 0
0 -1]
or if you have the preimage and image - before transformation and after, you can see what happened to the coordinates
Or you can just memorize the transformation matrices

Answer 2

http://www.mrjoselson.com/44%20matrix%20transformations.ppt
is a powerpoint I used this year to teach matrix transformations