Question

Points A(−1.5) and B(6) are marked on a number line. Find the coordinate of point M if it is known that AM:MB=1:2. Find all possible answers.

Answer 1

M can have a coordinate of (-9) or (1) There are potentially 3 different places for point M to go. It can be placed to the left of point A, between points A and B, and to the right of point B. Let's check those three possibilities. 1. Left of point A. This works if the distance between M and A is the same as the distance between A and B. So distance between A and B = 6 - (-1.5) = 6 + 1.5 = 7.5 So the location for M would be -1.5 - 7.5 = -9 So point M can have the value of -9. 2. Between A and B. This would also work. Since we want a 1:2 ratio, place M one third of the way from A to B. Since we already know the distance between A and B to be 7.5, that means that we should add 7.5/3 = 2.5 to the value of A. So -1.5 + 2.5 = 1 So point M can also have the value of 1. 3. To the right of point B This won't work. Point B will always be closer to M than point A will be. So it's impossible to get a ratio of 1:2.