Find the coordinates of the point where the line joining A(3, 4, 1) and B(5, 1, 6) crosses the xy-plane.

Let the plane XY divides the points A(3,4,1) and B(5, 1, 6) in ratio k:1.


Hence, using section formula (, we get



On XY plane, Z co- ordinate of every point be zero, therefore



6k + 1 = 0



The ratio is 1:6 externally in XZ plane which divides the line joined from points A and B.


1