The elements in the first 3 columns are the coefficients of system of equations.
The 4th column are the constants of the system of equations.
This is a system of 3 equations.
Let's write the system using the variables x, y, and z. Shown below:
![\begin{gathered} 1x+1y+0z=3 \\ 0x+4y+1z=-5 \\ 1x+0y-1z=4 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/pbaj2xpomggzp4l2iqwbzurehykhjwe1br.png)
Let's simplify and write the equations:
![\begin{gathered} x+y=3 \\ 4y+z=-5 \\ x-z=4 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/5l27swherm8mvtkt32hq9rrpgkro6w2mq4.png)