Question

find the measure of an angle which is complement of itself

Answer 1

Let the angle be x°
complementary property will be applied then,
x + x = 90°
=> 2x = 90°
=> x = 45°

Answer 2

Let the angle be X . Its complement will be 90° - X . Then ,
X = 90 - X
=> X + X = 90°
=> 2X = 90°
=> X = 90°/2
=> X = 45°

Hence, the angle is 45°