(a)
If the sum of the measures of two angles is 90° they are known as complementary angles.
- Let the value of unknown angle be x.
According to the question
⇨x + 40° = 90°
⇨x = 90° - 40° [Subtract]
⇨x = 50°
Complement angle is 50°
____________________
(b)
If the sum of the measures of two angles is 180° they are known as supplementary angles.
- Let the value of unknown angle be x.
According to the question
⇛x + 63° = 180°
⇛x = 180° - 63° [Subtract]
⇛x = 117°
Supplement angle is 117°