In a quadrilateral ABCD, ∠A+∠Cis 2 times ∠B+∠D. If ∠A=140∘ and ∠D=60∘,then ∠B=

In a quadrilateral ABCD, ∠A+∠Cis 2 times ∠B+∠D. If ∠A=140�

1.	In a quadrilateral ABCD, ∠A+∠Cis 2 times ∠B+∠D. If ∠A=140∘ and ∠D=60∘,then ∠B=
Answer» In a quadrilateral ABCD, $∠ A + ∠ C$ is 2 times $∠ B + ∠ D$ . If $∠ A = 140^{\circ} a n d ∠ D = 60^{\circ}, t h e n ∠ B =$