Another question i'm having trouble with:

You have a square located about the origin with vertices A(1,0), B(0,1),

C(-1,0) and D(0,-1). There are a total of eight transformations that map ABCD onto itself. Rotation through 90 degrees and reflection in the x-axis are two transformations that do this.

Find the other 6 transformations and the transformation matrix to go with it. (Hint they all follow a similar pattern)

Plz help!