Q23 of 28 Page 93

A man is standing on the deck of a ship, which is 10 m above the water level. If he observes the angle of elevation of the top of a hill as 60° and the angle of depression of the base of the hill as 30°, then find the distance of the hill from the ship and the height of the hill.


Let height of the deck is AB, Height of the Hill is CD.


Given, AB = 10, ∠CBE = 600, ∠EBD = 30o.


AB = DE (ABED is a rectangle)


in ∆BED,




BE = 10√3


in ∆CBE,



CE = 10√3 × √3


CE = 30


Total height of the tower = 40


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