Question

A 13m long ladder reaches a window of a building 12m above the ground. Determine the distance of the foot of the ladder from the building. 

Answer 1

Let AB and AC be the ladder and height of the building.
It is given that :
AB = 13 m and AC = 12 m
We need to find distance of the foot of the ladder from the building, i.e, BC.
In right-angled triangle ABC, we have: 

  

`AB^2=AC^2+BC^2` 

⟹ `BC=sqrt(13^2-12^2)` 

=`sqrt(169-144)` 

`=sqrt25` 

=5 m 

Hence, the distance of the foot ladder from the building is 5 m