Angle of Elevation • The angle between the line of sight and the horizontal when an observer looks upward. Line of Sight Horizontal
Example 1 • Little Suzie let go of her balloon. It floated to the top of the gym, 50 feet above the ground. Her big brother Matthew is standing 60 feet away. What is the angle of elevation from him to the balloon? 50 ft xo 60 ft
Example 2 • Find the angle of elevation of the sun when a 7.6 meter flagpole casts an 18.2 m shadow. Round to the nearest tenth. 7.6 m xo 18.2 m
Horizontal Line of Sight Angle of Depression • The angle between the line of sight and the horizontal when an observer looks downward. All “angle of depression” problems will require you to re-draw the triangle!!!
Example 1 • A hiker is standing on the top of a 100 yard cliff. He is looking down at a cabin on the ground below him. The cabin is 230 yards from the base of the cliff. What is the angle of depression? 230 yd 100 yd 100 yd 230 yd
Example 2 • A sledding run is 300 yards long with a vertical drop of 27.6 yards. Find the angle of depression of the run. 300 yd 27.6 yd 27.6 yd
Example 3 • A salvage ship uses sonar to determine that the angle of depression to a wreck on the ocean floor is 13o. The depth chart shows that the ocean floor is 40 meters below the surface. How far must a diver lowered from the ship walk along the ocean floor to reach the wreck? x 40 m 40 m x