Let L be the perp. bisector of AB with M the midpoint of AB. Then A', B', M', and L' are the images under the affine transformation t of the respective A, B, M, and L. Prove the following or find a counterexample

a) L' intersects A'B' at M'

b) L' is the perpendicular bisector of A'B'

I think a) is true and b) is false, but I'm having trouble with the proof/counterexample.