Answer: 18°
Explanation:
Complementary angles are any two angles whose sum is 90 degrees. Hence, if angles x and y are complimentary, we can say
x + y = 90°
Therefore, the complimentary angle of 72° is obtained by subtracting 72° from 90°
i.e 90° - 72° = 18°
Thus, the complimentary angle of 72° is 18°