ACT Preparation / Unit 14 ACT 1321 short lesson, about 20 seconds
Angles of Elevation and Depression
Captions available
The idea
An angle of elevation is measured up from the horizontal to a line of sight; an angle of depression is measured down from the horizontal.
In practice
Looking up at 25° to the top of a tower 100 meters away, the height is 100 tan 25°, about 46.6 meters.
Where people slip
Both angles are measured from the horizontal, never from the vertical.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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