Which statement describes supplementary angles?

Which statement describes supplementary angles?

• A. Two angles whose sum is 90 degrees.
• B. Two angles that share a vertex and side.
• C. Two angles whose sum is 180 degrees.
• D. A polygon with four sides.

Answer: (C)

Supplementary angles are two angles whose measures add up to 180 degrees. This often happens when the two angles form a straight line, filling the entire straight angle. For example, if one angle is 120 degrees, the other must be 60 degrees to reach 180. This is different from complementary angles, which add to 90 degrees, not 180. Just sharing a vertex and a side describes adjacent angles, which are next to each other, but they don’t have to add to 180 unless specifically formed as a linear pair. A polygon with four sides is a quadrilateral, which isn’t about the sum of two angles. So the statement that describes supplementary angles is the one where the two angles’ measures add up to 180 degrees.

Supplementary angles are two angles whose measures add up to 180 degrees. This often happens when the two angles form a straight line, filling the entire straight angle. For example, if one angle is 120 degrees, the other must be 60 degrees to reach 180.

This is different from complementary angles, which add to 90 degrees, not 180. Just sharing a vertex and a side describes adjacent angles, which are next to each other, but they don’t have to add to 180 unless specifically formed as a linear pair. A polygon with four sides is a quadrilateral, which isn’t about the sum of two angles.

So the statement that describes supplementary angles is the one where the two angles’ measures add up to 180 degrees.