a passenger on a cruise ship is positioned 42m above the water level and is admiring a tropical island in the distance. One end of the island is at a true bearing of 028 degrees and has an angle of depression of 11 degrees. The other end is at a true bearing of 118 degrees and has an angle of depression of 19 degrees. How long is the island to the nearest metre.

Question

Narad · Answer

Make a sketch and you'll get 3 right angled triangles.
And the length of the island is
$$= \sqrt{\left( (42\tan79º)^{2} +(42\tan71º)^{2}\right)}$$