They can be joined together to form a right angle. They can be joined together to form a straight angle. The complement of an angle x° is (90 - x)°. The difference between complementary angles and supplementary angles are given in the table below: Supplementary AnglesĪ pair of angles are said to be supplementary if their sum is 180 degrees.Ī pair of angles are said to be complementary if their sum is 90 degrees. When complementary angles can be considered as two parts of a right angle, the supplementary angles are the two parts of a straight angle or a 180-degree angle. They can either be adjacent or non-adjacent. The complementary and supplementary angles are those that add up to 90 degrees and 180 degrees respectively. When non-adjacent complementary angles are put together, they form a right angle.Ĭomplementary Angles and Supplementary Angles Thus, these two angles are non-adjacent complementary angles. Also, they add up to 90 degrees that is, ∠ABC + ∠PQR = 50° + 40° = 90°. In the figure given below, ∠ABC and ∠PQR are non-adjacent angles as they neither have a common vertex nor a common arm. Non-adjacent Complementary Angles: Two complementary angles that are NOT adjacent are said to be non-adjacent complementary angles. Thus, these two angles are adjacent complementary angles. They also add up to 90 degrees, that is ∠COB + ∠AOB = 70° + 20° = 90°. In the figure given below, ∠COB and ∠AOB are adjacent angles as they have a common vertex 'O' and a common arm 'OB'. There are two types of complementary angles in geometry as given below:Īdjacent Complementary Angles: Two complementary angles with a common vertex and a common arm are called adjacent complementary angles. If the sum of two angles is equal to the measurement of a right angle then the pair of angles is known as the complementary angle.

A supplementary angle