# Using section formula, prove that the three points (-4, 6, 10), (2, 4, 6) and (14, 0, - 2) are collinear. Also find the ratio in which point B divides the join of A and C.

Let point B (2, 4, 6) divides the join of A (-4, 6, 10), C (14, 0, -2) in the ratio k : 1

∴ The co-ordinates of point B are

On putting

When

∴ Point B (2, 4, 6) divides the join of A (-4, 6, 10) and C (14, 0, -2) in the ratio internally. Hence, A, B, C are collinear and ratio of division at B is 1 : 2 internally.