Question

ABCD is a cyclic quadrilateral. If ZBCD = 100° and ZABD - 300 then ZADB is​

Answer 1

Answer:

We have;

∠BCD=100°;∠ABD=50°

We know that in a cyclic quadrilateral the sum of diagonal angles is 180°

∠BCD+∠DAB=180°

⟹∠DAB=80°

Now; in ΔADB;

∠ADB+∠DAB+∠ABD=180°

⟹∠ADB+80°+50°=180°

Hence;∠ADB=50°

solution