The given operation involves just swapping the two rows, so carrying out [tex]R_1\leftrightarrow R_2[/tex] on the matrix gives
[tex]\left[\begin{array}{cc|c}5&5&5\\1&-\dfrac23&5\end{array}\right]\to\left[\begin{array}{cc|c}1&-\dfrac23&5\\5&5&5\end{array}\right][/tex]
