Question

when the last row of the matrix is say (o o o o ) what does it mean?

Answer 1

I think it might mean that the matrix is in reduced row echelon form.

Did u start off with a different matrix in order to reach it?

Answer 2

i means that their is a free variable in the solution.

Answer 3

If you have a row of zeros then one of your variables is independent (free)

Answer 4

OK, meaning the number of independent equations is less than the number of variables.

But u find out how many independent equations u have by reducing the matrix, no?

Answer 5

Yes usually.