Question

A ladder 17 metre long reaches a window which is 8 metre above the ground on one side of the street. Keeping it's foot at the same point, the ladder is turned to the other side of the street to reach a window at a height of 15 metre. Find the width of the street

Answer 1

Length of ladder=AC=15m
Height of window from ground
in first case AB=9m
ABC is right angled triangle
Ac^2=AB^2+BC^2
BC=12m
In second case
Let CE be length of ladder=15m
Height of window from ground=DE=12m
Triangle CDE is a right angled triangle
CE^2=DE^2+CD^2
CD=9m
Width of street=BC+CD=9+12=21m