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Question
The foot of a ladder is 6 m away from its wall and its top reaches a window 8 m above the ground. If the ladder is shifted in such a way that its foot is 8 m away from the wall, to what height does its top reach?
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Solution
Let the height of the top be x m.
In right angled ΔACB,
AC2 = AB2 + BC2 ...[By Pythagoras theorem]
⇒ AB2 = AC2 – BC2
⇒ x2 = (10)2 – (8)2 = 100 – 64
⇒ x = `sqrt(36)`
⇒ x = 6 m
Hence, the height of the top is 6 m.
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