Answer:
The angles are 23° , 67°.
Step-by-step explanation:
   If sum of two angles is 90°, then they are called complementary angles.
Let one angle be 'x'.
Its complement = 2*x + 21 = 2x + 21
x + 2x + 21 = 90°
   3x  + 21 = 90
Subtract 21 from both sides,
       3x = 90 - 21
       3x = 69
Divide both sides by  3,
         x = 69/3
         x = 23°
Its complement = 2*23 + 21
             = 46 + 21
             = 67°
Two complementary angles are 67° and 23°.