Evaluate
$$
\left(\begin{array}{lll}
2 & 3 & 1 \\
0 & 1 & 5 \\
3 & 7 & 2
\end{array}\right)^{-1} \bmod 17
$$
by doing row reduction modulo 17 on the augmented matrix
$$
\left(\begin{array}{llllll}
2 & 3 & 1 & 1 & 0 & 0 \\
0 & 1 & 5 & 0 & 1 & 0 \\
3 & 7 & 2 & 0 & 0 & 1
\end{array}\right)
$$