Chapter 1.1, Problem 16E

In Exercises 16-18, determine whether the given $\left(2\times 3\right)$ system of linear equations represents coincident planes (that is, the same plane), two parallel planes, or two planes whose intersection is a line. In the latter case, give the parametric equations for the line; that is, give equations of the form $x=at+b$, $y=ct+d$, $z=et+f$.

$\begin{array}{rll}2x_1+x_2+x_3& =& 3\\ -2x_1+x_2-x_3& =& 1\end{array}$