Supplementary angles are two angles whose sum is 180 degrees while complementary angles are two angles whose sum is 90 degrees.

When the sum of two angles is 90 degree they are called?

Two angles are called complementary if their measures add to 90 degrees, and called supplementary if their measures add to 180 degrees.

When the sum of two angles is 180 degrees?

Supplementary angle: "if the sum of two angles is 180 degrees, or a straight angle, they are called supplementary angles."