Question 1103392
7x+y+5z=2
5x-8y-z=6
x-6y-4z=-9
Take out the letters (variables) and plus signs add 1 if there is no coefficient
<pre>
|7  1  5 | 2|
|5 -8 -1 | 6|
|1 -6 -4 |-9|
</pre>