Question

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 ladder from the base of the building?

Answer 1

Let AB be the building and CB be the ladder.

Then, AB = 24 m, CB = 25 m

And ∠CAB = 90°

By Pythagoras Theorem,

CB² = AB² + CA²

⇒ CA² = CB² – AB²

= 25² – 24²

= 625 – 576

= 49

⇒ CA = 7 m

Hence, the distance of the foot of ladder from the building is 7 m.