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 $=$  

(Note: Enter the number in the first box and the unit (short form) in the second box.)