A ladder 25 m long just reaches the top of a building 24 m high from the ground. What is the distance of the foot of the ladder from the building?
Let BC be the ladder placed against the wall AB. The distance of the ladder from the wall is the base of the right angled triangle as building stands vertically straight to the ground.
By Pythagoras theorem
(BC)2 = (AB)2 + (AC)2
(25)2 = (24)2 + (x)2
x = 7
the distance of ladder from the wall is 7m
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