There are two windows on the wall of a building that need repairs. A ladder 30 m long is placed
against a wall such that it just reaches the first window which is 26 m high. The foot of the
ladder is at point A. After the first window is fixed, the foot of the ladder is pushed backwards
to point B so that the ladder can reach the second window. The angle made by the ladder with the
ground is reduced by half, as a result of pushing the ladder. The distance between points A and B is