Angle of Elevation

Trig functions are used regularly when the distance to an object is needed and that distance is difficult to obtain using standard tools.  For example an object that is a great distance away from a person's point of view.  Those distances are described by two situations, an angle of elevation and an angle of depression.

An angle of elevation is the measure of an angle from the horizontal to the line of sight as a person is looking up at an object.  See the drawing below.


In the diagram above, the sight line is the segment from the eye (A) to the object (C) and the measure of the angle from the horizontal to the sight line is the angle of elevation.  In order to use trig functions within situations involving the angle of elevation, draw a vertical line from the object to the horizontal line creating the right triangle.