The direction ratios of the line perpendicular to the lines 
and 
are proportional to
We have,
The direction ratios of the given lines are proportional to 2,-3,1 and 1,2,-2.
The given lines are parallel to the vectors →
and 
Vector perpendicular to the given two lines is →
Hence, the direction ratios of the line perpendicular to the given two lines are proportional to 4,5,7.
1