The foot of a ladder 25 m long is 7 m from the base of the building. If the top of the ladder slips by 4 m, then by how much distance will the foot of the ladder slide?
Answer & explanation
Correct answer: option 4
⇒ Using pythagoras theorem in 1st figure i.e; triangle ABC, we get
⇒ AB = 24 m
Now,
Applying Pythagoras theorem in triangle DBE
⇒ \( {DE }^{ 2} \) = \( {DB }^{2 } \) + \( {BE }^{2 } \)
⇒ \( {25 }^{ 2} \) = \( {20 }^{2 } \) + \( {BE }^{2 } \)
⇒ 625 - 400 = \( {BE }^{2 } \)
⇒ \( {BE }^{2 } \) = 225
⇒ BE = 15m
⇒ CE = 15 - 7 = 8m.
Therefore, foot of the ladder slide by 8m.