Question

a ladder reaches a window which is 12 m above the ground on one side of street, keeping its foot at the same point, the ladder is turned to the other side of the street to reach a window 9 m high. find the width of the street if the length of the ladder is 15 m

Answer 1

In △ABC△ABC

AB2+BC2122+BC2⟹BC=AC2=152=9mAB2+BC2=AC2122+BC2=152⟹BC=9m

In △DCE△DCE

DE2+CE292+CE2⟹CE2CE=DC2=152=225−81=12mDE2+CE2=DC292+CE2=152⟹CE2=225−81CE=12m

Hence the width of the street is BC + CE = 9+12 = 21m