Find all matrices that commute with the given matrix A. (The following is all one matrix).

[2 3]

[-3 2]

I let B = the matrix with four variables w, x (top row) y, z (bottom row). I then found AB and BA. I then had the following equations, and this is where I'm stuck.

2w + 3y = 2w - 3x

2x + 3z = 2x + 3w

2y - 3w = 2y - 3z

2z - 3x = 2z + 3y

Any knowledge on where to go from here would be great.