H = Height of the lighthouse = 200 ft
L = Distance between the lighthouse and a ship
theta = The angle of elevation = 21 °
tan theta = H / L
tan 21 ° = 200 / L Multiply both sides b L
L tan 21 ° = 200 Divide both sides by tan 21 °
L = 200 / tan 21 °
L = 200 / 0.383864
L = 521,01786 ft
The angle of elevation from a ship in the ocean to the top of a lighthouse is 21deg. If the lighthouse is 200 ft. tall, how far out is the boat? Be sure to show work for partial credit.
1 answer