How to express a vector as a linear combination of others? I have 3 vectors, $(0,3,1,-1), (6,0,5,1), (4,-7,1,3)$, and using Gaussian elimination I found that they are linearly dependent. The next question is to express each vector as a linear combination of the other two. Different resources say just to use Gaussian elimination, but I just end up with a matrix in RREF. How can I find different vectors as a linear combination of others?

Since (0,3,1,-1) is a linear combination of (6,0,5,1) and (4,-7,1,3), we can write 
$(0,3,1,-1) = a(6,0,5,1) + b(4,-7,1,3)$. This gives us 4 relations to solve for a and b. We can proceed similarly for the other two vectors.
