21. Five mark example problem VIII

As observed from the top of a \(60 \ m\) high lighthouse from the sea level, the angles of depression of two ships are \(28^{\circ}\) and \(45^{\circ}\). If one ship is exactly behind the other on the same side of the lighthouse, find the distance between the two ships. (\(tan \ 28^{\circ} = 0.5317\))

 

Answer:

 

The distance between the two ships \(=\)  

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