Similarly, what has happened if you have an entire row of zeros in a matrix?
The Null Space takes your b-vector to be 0, and it sends x to 0. However, if there is a row of all zeros in your matrix, then that means that N(A) is nontrivial and there's a free variable.
Furthermore, can a matrix with a row of zeros have an inverse? If a matrix has a row of zeroes or a column of zeros, the determinant of the matrix is 0. Hence, they are not invertible.
Considering this, what does a column of zeros mean in a matrix?
A zero column in reduced row echelon form means that the corresponding variable is a free variable.
What is a non zero row in a matrix?
A row matrix has 1 or more columns but only 1 row, like this: (1 2 3). A column matrix is the transpose of a row matrix and has several rows but only 1 column. 1. 3. The non-zero part of the requirement just means at least one element should be non-zero, like this: (0 0 3).