4. The sides AB and CD of a quadrilateral are produced as shown in Fig. 8.7. Prove that a + b = x

December 2023 1 0 Report

4. The sides AB and CD of a quadrilateral are produced as shown in Fig. 8.7. Prove that a + b = x + y

Answer:

1. angleD = 180-x

angle B =180-y

so, in quadrilateral ABCD a+b+180-x+180-y = 360 (property of quadrilateral)

now, a+b-x-y=360-(180+180)

a+b-x-y=0

a+b=x+y