If rref has only one argument, this argument is the augmented matrix
of the system (the matrix obtained by augmenting matrix A to the
right with the column vector B).
The result is a matrix [A1,B1] : A1 has zeros both above and under
its principal diagonal and has 1 on its principal diagonal, and the solutions
are the same as :
For example, to solve the system:
Hence x = - 2 and y = 4 is the solution of this system.
rref can also solve several linear systems
of equations having the same first member.
We write the second members as a column matrix.
Which means that (x = - 2 and y = 4) is the solution of the system
and (x = 0 and y = 1) is the solution of the system