If the distance from the boat to the lighthouse is 115 meters and the angle of elevation is 42°, which of the following equations will find the height of the lighthouse?
a right triangle is formed from the distance between a boat and the bottom of a lighthouse, the height of the lighthouse, and the distance from the boat to the top of the lighthouse; the angle of elevation from the boat to the top of the lighthouse is x degrees.
tan 42° = y over 115
tan 42° = 115 over y
cos 42° = y over 115
cos 42° = 115 over y