Answer
$ \left[\begin{array}{ccc|c}
1 & 0 & -4& 5\\
0 &-1 & 26& -20 \\
2&-1&4&-3
\end{array}\right]$
Work Step by Step
The augmented matrix is
$\Rightarrow \left[\begin{array}{ccc|c}
1 & 0 & -4& 5\\
6 & -1 & 2& 10 \\
2&-1&4&-3
\end{array}\right]$
Perform $R_2\rightarrow -6R_1+ R_2$.
Multiply the first row by $-6$ and add to the second row.
$\Rightarrow \left[\begin{array}{ccc|c}
1 & 0 & -4& 5\\
-6(1)+6 &-6(0)+ (-1) & -6(-4)+2& -6(5)+10 \\
2&-1&4&-3
\end{array}\right]$
Simplify.
$\Rightarrow \left[\begin{array}{ccc|c}
1 & 0 & -4& 5\\
0 &-1 & 26& -20 \\
2&-1&4&-3
\end{array}\right]$.
