NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 5: Lines And Angles - Multiple Choice QuestionsQuestion 33
Class 7 - Mathematics - Unit 5: Lines And Angles - Multiple Choice Questions
Question. 33
In Fig. 5.27, a = 40°. The value of b is
(a)
(a) 20°
(b)
(b) 24°
(c)
(c) 36°
(d)
(d) 120°
Detailed Answer with Explanation:
Angles on a straight line: 2a + 5b = 180.
Substitute a=40: 80 + 5b = 180 ⇒ 5b=100 ⇒ b=20°.