Show that the shortest distance between the lines ` x=y+2a=6z−6a` and ` x+a=2y=−12z` is 2a .

Write the distance between the plane x-2y+z=6 and 2x-4y+2z=8

What is the angle between the lines x/1 = y/-2 = z/1 and x/4 = y/1 = z/-2 .

Find the distance between the two planes 2x+3y+4z=4 and 4x+6y+8z=12 .

Find the shortest distance between the lines (x-1)/(2) = (y-2)/(3) = (z-3)/(4) and (x-2)/( 3) = (y-3)/(4) = (z-5)/(5)