Question

a 15 metre long ladder Richard a window 12 metre high from the ground on placing it against a wall find the distance on the foot of the ladder from the wall​

Answer 1

Let AC be the ladder and A be the window.

Given: AC=15m, AB=12m, CB=am

In right angled triangle ACB,

(Hypotenuse)  

2

=(Base)  

2

+[Perpendicular)  

2

 [By Pythagoras theorem]

⇒(AC)  

2

=(CB)  

2

+(AB)  

2

 

⇒(15)  

2

=(a)  

2

+(12)  

2

 

⇒225=a  

2

+144

⇒a  

2

=225−144=81

⇒a=  

81

​  

=9cm

Thus, the distance of the foot of the ladder from the wall is 9m.