2 by 2 Matrix Transformations Interactive Investigation
Investigate matrix transformations of the 2-D plane by modifying the elements of a 2 by 2 matrix and observing the effect.
See if you can find matrices that produce 90, 180 and 270 degree rotations (clockwise or anticlockwise), reflections (in y=0, x=0, y=x or y=-x) and enlargements.