Iteme

The row equivalent reduced row echelon form is

\begin{equation*} \left[ \begin{array}{rrr|r} 1 \amp 0 \amp 0 \amp -1 \\ 0 \amp 1 \amp 0 \amp 2 \\ 0 \amp 0 \amp 1 \amp 1 \\ \end{array} \right]. \end{equation*}

This system has the single solution \((-1,2,1)\text{.}\)

in-context