Complementary, supplementary and vertically opposite angles

Complementary angles
If the sum of the measure of two angles is 90°, then the two angles are called complementary, and each of them is called a complement of the other.

If m∠AOB = 90°, then ∠AOD & ∠BOD
are complementary angles

Example:
A 20° angle and a 70° angle are complementary.
Similarly a 30° and a 60° angle are complementary.

Definition

Supplementary angles
If the sum of the measures of two angles is equal to 180° (two right angles) then the
angles are called supplementary, and each of them is called a supplement of the other.

Since m∠AOD + m∠BOD =180°, the angles AOD and BOD are called supplementary angles

Example:

A 30° and 150° angles are supplementary.

Similarity a 60° and 120° angle are also supplementary.