Q10 of 107 Page 12

The angles of depression of two ships from the top of a light house are 45° and 30° towards east. If the ships are 100 m apart, the height of the light house is


Here AD = h meter is the tower


The ships B and C are 100 m apart so BC = 100 m


In Δ ACD


tan 45° =


CD = h (∵ tan 45° = 1)


In Δ ABD


tan 30° =


=


h =


h= 100 + h


h = m


On rationalizing the denominator


h =


h = 50 (m

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