Q38 of 107 Page 12

Two men on either side of the cliff 80 m high observes the angles of elevation of the top of the cliff to be 30° and 60° respectively. Find the distance between the two men.

In fig. AB be the height of the cliff.


Let the distance between the two men is DC.


DC = m.


In ∆ABC


tan 60° =


√3 =


√3 = 80



------(1)


In ∆ABD



tan 30° =



--------(2)


Adding eqn. (1) and (2) we get,


=


⇒ ⇒ ⇒ 184.75 m.


Therefore distance between two men is 184.75 m.


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