Question

Lsub1 : x=1+2t, y=2-t, z=4-2t

Lsub2 : x=9+t , y=5+3t, z=-4-t

Lsub1 and Lsub2 intersect at the point (7,-1,-2).

Find parametric equations for the line that is perpendicular to Lsub1 and Lsub2 passes through their point of intersection.

* if possible, please draw me the picture. I can't figure out how this line can perpendicular to Lsub1 and Lsub2.

Thank you very much.