1. The problem statement, all variables and given/known data I'm doing a proof in which I need to show: given that AX = 0, AVX=0 where V is invertible. Also, given that AVY = 0, then AY = 0. 2. Relevant equations 3. The attempt at a solution I can't remember from the previous course I took how to do this. I know that I can multiply from the left or right by V-1, but seeing as V is in the middle that won't work. This is part of a larger proof, if it would make more sense to have the entire question let me know.