Determine whether the lines are coincident, parallel,
intersecting, or skew. If the lines intersect, find the point of
intersection.
a) l1: (2,-4,0)+ t<6,2,-2) and l2: x=5-t, y=1-1/3t, z=2+1/3t b) l1: x=2t, y=3-2t, =-1+5t and l2: (3,0,-2) + t<1,0,1>
c) l1: (3,1/2,0) + t<2,-3/4, 2> and the line through the
points P(4,0,2) and Q(-5,3,-4)