Given a matrix used to perform Gaussian Elimination like this:
$$ \begin{bmatrix} 1 & -3 & | & 1 \\ 2 & -7 & | & 3 \end{bmatrix} $$
Which would be derived from a system of equations like this:
$$ \begin{cases} x - 3y = 1 \\ 2x - 7y = 3 \end{cases} $$
Do the different "sides", i.e. the parts that come from the right hand side of the equation and the part that comes from the left hand side of the equation, respectively, have names?