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A 15m long ladder reached a window 12m high form ground on placing it against a wall at a distance x. Find the distance of the foot of the ladder from the wall .

User Kjakeb
by
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1 Answer

4 votes

Answer:

9m

Explanation:

First of all, I need to asume that the wall is perpendicular to the floor, so we have a right triangle with both the floor (a) and the wall (b) as legs and the ladder as the hypotenuse. This permit us to use Pitgoras' theorem:

a^2 + b^2 = 15^2

As the wall has 12m:

a^2 + 12^2 = 15^2

a^2 + 144 = 225

a^2 = 225 - 144

a^2 = 81

Applying sqr root

a =
√(81)

a = 9

User Wazza
by
9.3k points