Question

Quadrilateral ABCD is a cyclic if AD//BC and <B=70 then find all angles of quadrilateral ABCD​

Answer 1

Answer:

110°

Step-by-step explanation:

angle D = angle B = 70°

angle A + angle B = 180°                       [by linear pair]

angle A = 180 - 70

             = 110°

angle C = angle A = 110°

Answer 2

Answer:

proof:- <b+<d=180 (since opp. <s. of a cyclic quad.)

=> <d=180-<b

=> <d=180-70

=> <d=110

since AD//BC and cd is transversal

<d+<c=180 ( co.int. <s)

=> <c=180-110

=> <c=70

similarly, <a=110

hence, <a=110 , <b=70, <c=70 & <d=110.