Finite Math Examples

$[\begin{array}{c} 5 & 1 & 1 & 0 & 0 & 0 & 70 \\ 9 & 2 & 0 & 1 & 0 & 0 & 90 \\ 1 & 1 & 0 & 0 & 1 & 0 & 80 \\ - 2 & - 9 & 0 & 0 & 0 & 1 & 0 \end{array}]$

Step 1

$[\begin{array}{c} 5 & 1 & 1 & 0 & 0 & 0 & 70 \\ 9 & 2 & 0 & 1 & 0 & 0 & 90 \\ 1 & 1 & 0 & 0 & 1 & 0 & 80 \\ - 2 & - 9 & 0 & 0 & 0 & 1 & 0 \end{array}]$