Two angles whose sum is 180 degrees are called supplementary angles.

Explanation:

• If angle A and angle B are supplementary, then:

A+B=180∘A+B=180^\circ A+B=180∘

• These angles can be adjacent (forming a straight line) or non-adjacent.

Examples:

• 120° and 60° are supplementary because 120∘+60∘=180∘120^\circ +60^\circ =180^\circ 120∘+60∘=180∘.
• 90° and 90° are also supplementary.

If you want, I can help you with problems involving supplementary angles!