What Are Two Angles With a Common Side and No Interior Points Called?

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Two angles that share a common side and a common vertex, but have no common interior points are called adjacent angles, often abbreviated as “adj.” Adjacent angles lie side by side to each other. Their shared common arm is also called a ray or an edge.

There are three types of adjacent angle pairs. Adjacent angles which add up to 90 degrees, or form a right angle together, are called complimentary angles. Adjacent angles which sum to 180 degrees, a straight line, are known as supplementary angles. Adjacent angles that form a complete angle, 360 degrees or one turn, are called conjugate or explementary angles.