Answer:
Complementary angles.
Explanation:
Complimentary angles means sum of angles = 90°
Supplementary angles of linear pair means sum of pair of angles = 180°
As shown in the picture attached, sum of both the angles 'a' and 'b' is equal to 90°,
a + b = 90°
Angles 'a' and 'b' will be complementary angles.