In geometry, a linear pair of angles is a pair of adjacent angles formed when two lines intersect each other.

Adjacent angles are formed when two angles have a common vertex and a common arm but do not overlap.

The linear pair of angles are always supplementary as they form on a straight line. In other words, the sum of two angles in a linear pair is always 180 degrees.

When two lines intersect each other at a single point, linear pairs of angles are formed.

If the angles so formed are adjacent to each other after the intersection of the two lines, the angles are said to be linear.

If two angles form a linear pair, the angles are supplementary, whose measures add up to 180°. Hence, a linear pair of angles always add up to 180°.