Answer
$\left[\begin{array}{rrrr}
3 & 2 & -1 & 1\\
1 & 0 & -1 & 0\\
0 & 3 & 1 & -1
\end{array}\right]\left[\begin{array}{l}
x_{1}\\
x_{2}\\
x_{3}\\
x_{4}
\end{array}\right]=\left[\begin{array}{l}
0\\
5\\
4
\end{array}\right]$
Work Step by Step
Coefficient matrix: $A=\left[\begin{array}{llll}
3 & 2 & -1 & 1\\
1 & 0 & -1 & 0\\
0 & 3 & 1 & -1
\end{array}\right]$
Constant matrix: $B=\left[\begin{array}{l}
0\\
5\\
4
\end{array}\right]$
Uknowns: $X=\left[\begin{array}{l}
x_{1}\\
x_{2}\\
x_{3}\\
x_{4}
\end{array}\right]$
$AX=B$
$\left[\begin{array}{llll}
3 & 2 & -1 & 1\\
1 & 0 & -1 & 0\\
0 & 3 & 1 & -1
\end{array}\right]\left[\begin{array}{l}
x_{1}\\
x_{2}\\
x_{3}\\
x_{4}
\end{array}\right]=\left[\begin{array}{l}
0\\
5\\
4
\end{array}\right]$
