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प्रश्न
Foot of a 10 m long ladder leaning against a vertical wall is 6 m away from the base of the wall. Find the height of the point on the wall where the top of the ladder reaches.
उत्तर
Let AB be a vertical wall and AC = 10 m is a ladder.
The top of the ladder reaches to A and distance of ladder from the base of the wall BC is 6 m.
In right angled ΔABC,
AC2 = AB2 + BC2 ...[By pythagoras theorem]
⇒ (10)2 = AB2 + (6)2
⇒ 100 = AB2 + 36
⇒ AB2 = 100 – 36 = 64
∴ AB = `sqrt(64)` = 8 cm
Hence, the height of the point on the wall where the top of the ladder reaches is 8 cm.
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