9000019909

The augmented matrix of a system of three equations with three unknowns is the following matrix $M^{\prime }$. Identify the matrix which is row equivalent to $M^{\prime }$. $$M^{\prime }=\left(\begin{array}{cccc}1& 2& 4& 14\\ -1& 0& 3& 7\\ 3& 1& -2& 42\end{array}\right)$$