Answer
The system is inconsistent and has no solutions.
Work Step by Step
The augmented matrix is given by
$$\left[ \begin {array}{cccc} 1&2&1&8\\ -3&-6&-3&-21
\end {array} \right]
.
$$
Multiply the first row by $3$ and adding it the second row , we get
$$\left[ \begin {array}{ccccc} 1&2&1&8\\ 0&0&0&3\end {array} \right].
$$
Now, the crossposting system is given by
$$
\begin{array}{l}
x+2y+z&=8 \\
0 z&=3.
\end{array}
$$
The above system is inconsistent and has no solutions.
