Final answer:
A linear pair of angles is two angles that share a common vertex and a common side, forming a straight line.
Step-by-step explanation:
A linear pair of angles is Option 1: two angles that share a common vertex and a common side, and together form a straight line. This means that the sum of the two angles is always 180 degrees. For example, if one angle measures 60 degrees, the other angle will measure 120 degrees.
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