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प्रश्न
A ladder is placed in such a way that its foot is at a distance of 15m from a wall and its top reaches a window 20m above the ground. Find the length of the ladder.
उत्तर
Let the height of the window from the ground and the distance of the foot of the ladder from the wall be AB and BC, respectively.
We have :
AB = 20 m and BC = 15 m
Applying Pythagoras theorem in right-angled ABC, we get:
`AC^2=AB^2+BC^2`
`⟹AC= sqrt(20^2+15^2)`
`=sqrt(400+225)`
`=sqrt625`
=25 m
Hence, the length of the ladder is 25 m.
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