Echelon form
Task number: 3246
By use of elementary transformations, reduce the following matrix to the echelon form.
Variant 1
\( \begin{pmatrix} 2 & 3 & 4 & 5 \\ 3 & 0 & 2 & -3 \\ 7 & 6 & 10 & 7 \\ \end{pmatrix} \)
Variant 2
\(\begin{pmatrix} 2 & -3 & 13 & 18 \\ 6 & -9 & 7 & 10 \\ 2 & -3 & -3 & -4 \end{pmatrix} \)
Variant 3
\(\begin{pmatrix} 1 & 2 & -1 & 1 \\ 2 & -1 & 4 & 10 \\ 1 & 0 & 3 & -5 \\ 2 & 5 & 2 & 2 \\ \end{pmatrix} \)
Variant 4
\(\begin{pmatrix} 1 & -1 & 1 & 2 \\ 1 & 8 & 7 & -7 \\ 1 & 2 & 3 & -1 \\ 1 & 5 & 5 & -4 \\ \end{pmatrix} \)