Exercise 4.2
1. Which of the following pairs of angles are complementary?
(a)
(b)
(c)
Solution:
2. Find the complementary angles of the following:
(i) 25°
Solution:
90° - 25° =
(ii) 40°
Solution:
90° - 40° =
(iii) 89°
Solution:
90° - 89° =
(iv) 55°
Solution:
90° - 55° =
3. Two angles are complement to each other are also equal. Find them.
Solution:
Two angles are complementary if their sum is 90°. If the two angles are also equal, we can represent each angle as x.
Since they are complementary:
x + x =
x =
Thus, the two angles are 45° each.
4. Manasa says, "Each angle in any pair of complementary angles is always acute". Do you agree? Give reason.
Solution:
Because the sum of the angles must be