Answer:
Angles are measure of rotation, along with its direction of rotation. The supplement angle of 77° is 103°
How to find the supplement angle of an angle?
Supplement angle of an angle is such that sum of both of them comes as 180°
Thus, if an angle is of A°, then its supplementary angle is 180° - A°
For the given case, we let the first angle be of A° = 77°, then its supplementary angle with measure B° is:
Thus, The supplement angle of 77° is 103°
