9.3 Angles of Elevation and Depression

SWBAT…

To use angles of elevation and depression to solve problems

Angle of elevation

The angle of elevation of an object as seen by an observer is the angle between the horizontal and the line from the object to the observer's eye (the line of sight).

Angle of Depression

If the object is below the level of the observer, then the angle between the horizontal and the observer's line of sight is called the angle of depression.

Example From the top of a vertical cliff 40 m

high, the angle of depression of an object that is level with the base of the cliff is 34º.  How far is the object from the base of the cliff?

Example 2

A man stands on a building and sees his friend on the ground. If the building is 70 m tall and the angle of depression is 35o, how far is the man from the building?

Class work

Page 484 # 1 – 23

Homework page 485 # 33, 34, 37-43