Included angle
From Latin: includere "to shut in, enclose"
Definition: The angle made by two lines with a common vertex
Included angle - the angle between two given lines that meet at a point

When two lines meet at a common point (vertex) the angle between them is called the included angle. The two lines define the angle. So for example in the figure above we could refer to the angle ABC as the "included angle of BA and BC".

Or we could refer to "BA and BC and their included angle".

See also Included side

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Other angle topics


Angle Types

Angle relationships