The linear equations are always presented in the form.
Such a form consists of the variables, i.e., ax + by + c = 0. The linear equations are always presented in the straight-line form. In the ax + by + c = 0, a, b, & c are the form of real numbers. And in it, a & b will never equal zero.
In comparison, x & y are the forms of two variables, and c is always present in the same form.
When we see the two sets of linear equations together, they are always considered a pair of linear equations. And both sets of equation x & y variables are different from each other.