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प्रश्न
A 15 m long ladder reached a window 12 m high from the ground on placing it against a wall at a distance a. Find the distance of the foot of the ladder from the wall.
उत्तर
By applying Pythagoras theorem,
(15)2 = (12)2 + a2
225 = 144 + a2
a2 = 225 − 144
a2 = 81
a = 9 m
Therefore, the distance of the foot of the ladder from the wall is 9 m.
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