![Ex 3.1, 6 - Chapter 3 Class 8 Understanding Quadrilaterals - Part 3](https://d1avenlh0i1xmr.cloudfront.net/cddc5579-4dc9-4bca-8aa4-487e5d6ee6c3/slide21.jpg)
Ex 3.1
Last updated at April 16, 2024 by Teachoo
Ex 3.1, 6 Find the angle measure x in the following figures (b) Given ∠BAO = 90° ∠B = x ∠C = 70° ∠D = 60° Since OAD is a line ∠ BAO + ∠1 = 180° 90° + ∠1 = 180° ∠ 1 = 180° − 90° ∠1 = 90° In quadrilateral ABCD, Sum of all angles of a quadrilateral = 360° ∠A + ∠B + ∠C + ∠D = 360° 90° + x + 70° + 60°= 360° x + 220° = 360° x = 360° − 220 x = 140°