Question

A ladder 13 m long rests against a vertical wall. Its top reaches to a window on the wall at 12 m high. Find the distance of the foot of the ladder from the wall.

Answer 1

Given: Ladder length (hypotenuse) = 13 m, height reached on wall = 12 m.

Step-wise calculation: 

Let x = Distance of the foot of the ladder from the wall.

In the right triangle,

x² + 12² = 13²

x² = 13² – 12²

= 169 – 144

= 25

`x = sqrt(25)` 

= 5 m

The foot of the ladder is 5 m from the wall.