Answer
Thre are infinitely many solutions
Work Step by Step
Convert the last row in the equation. Translating row 3 of the matrix into equation form, we obtain, $0x+0y+0z=0$
$0=0$
This row does not add any information about the variable. Thus, drop it from the system which can be expressed as
$\left[ \left. \begin{matrix}
\begin{matrix}
1 & -1 & -2 \\
\end{matrix} \\
\begin{matrix}
0 & 1 & -10 \\
\end{matrix} \\
\end{matrix} \right|\begin{matrix}
2 \\
-1 \\
\end{matrix} \right]$
Convert it in equation, $\begin{align}
x-y-2z=2 & \\
y-10=-1 & \\
\end{align}$
Here, we have two equations and three variables so, we have an infinite number of solutions for these equations.
