Official solution
Let slope of line be m
\[ \therefore \] \[\left| {{{m - 3\sqrt 2 } \over {1 + 3\sqrt 2 m}}} \right| = \sqrt 2 \]
\[ \Rightarrow m - 3\sqrt 2 = \pm \,\sqrt 2 \pm 6m\]
\[ \Rightarrow m \mp 6m = \pm \sqrt 2 + 3\sqrt 2 \]
\[ \Rightarrow m = - {{4\sqrt 2 } \over 5}\] or \[{{2\sqrt 2 } \over 7}\]
Hence line can be
\[y - 3 = {{ - 4\sqrt 2 } \over 5}(x - 1)\]
\[ \Rightarrow 5y - 15 = - 4\sqrt 2 x + 4\sqrt 2 \]
\[ \Rightarrow 4\sqrt 2 x + 5y - (15 + 4\sqrt 2 ) = 0\]