1. The problem statement, all variables and given/known data http://img94.imageshack.us/img94/5227/nxnmatrix.png [Broken] 2. Relevant equations Rank(A) = the number of pivots in Matrix A. 3. The attempt at a solution I've spent some time rewriting the matrix and other operations. I really just feel like I'm banging my head against the wall. Not making any progress. Just need to be pointed in the right direction. Oh and the answer is "2." No idea how they get that. Thanks for any help in advance. Edit: For reference this problem is from Applied Linear Algebra by Olver. Problem 1.8.17.