The foot of a ladder is 6 m away from its wall and its top reaches a window 8 m above the ground. Find the length of the ladder. - Mathematics

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Sum

The foot of a ladder is 6 m away from its wall and its top reaches a window 8 m above the ground. Find the length of the ladder.

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Solution

Let the length of the ladder be x m.


In right angled ΔABC,

AC2 = AB2 + BC2  ......[By Pythagoras theorem]

⇒ (x)2 = (8)2 + (6)2

⇒ `sqrt((8)^2 + (6)^2)` = `sqrt(64 + 36)` = `sqrt(100)`

⇒ x = 10 m

Hence, the length of the ladder is 10 m.

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Chapter 6: Triangles - Exercise [Page 185]

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NCERT Exemplar Mathematics Class 7
Chapter 6 Triangles
Exercise | Q 157. (a) | Page 185

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