Two angles are said to be complementary to each other when the sum of the two angles gives 90°. To find the angle complementary to angle 80°25′, we subtract angle 80°25′ from angle 90°. i.e. 90° - 80°25′ = 90° - 80° 25/60 = 90° - 80° 5/12 = 9° 7/12 = 9° (7/12 x 60)' = 9°35' Therefore, the angle complementary to 80°25′ is 9°35'.