A15m 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 .

9m

Step-by-step 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 =

a = 9