Q128 of 142 Page 88

A 5.5 m long ladder is leaned against a wall. The ladder reaches the wall to a height of 4.4 m. Find the distance between the wall and the foot of the ladder.

Given:

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Let distance between the wall and the foot of the ladder = (AB) = xm


(BC)2 = (AC)2 + (AB)2


⇒ (5.5)2 = (4.4)2 + (x)2


⇒ (x)2 = (5.5)2 - (4.4)2


⇒ (x)2 = 30.35 – 19.36


⇒ (x)2 = 10.89 = (3.3)2


⇒ (x) = 3.3


Hence, distance between the wall and the foot of the ladder = (AB) = 3.3m


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