Question

Find the equation of the line intersecting the lines (x - a)/1 = y/1 = (z + a)/1 and (x + a)/1 = y/1 = (z + a)/2 and parallel to the line (x - a)/2 = (y - b)/1 = (z - 2a)/3.

Answer 1

. .. x2 = -a + r2, y2 = r2, z3 = -a + 2r2

So, direction ratio of PQ are (x2 - x1, y2 - y1, z2 - z1)

i.e. (r2 - r1 - 2a, r2 - r1, 2r2 - r1 - 2a)

Since, PQ is paralled to line