Answer
The matrix is neither in the row echelon form nor in the reduced row echelon form.
Work Step by Step
The matrix
$$
\left[\begin{array}{rrr}{-1} & {2} & {1} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right]
$$
is neither in the row echelon form nor in the reduced row echelon form.
