Question

ABCD is parallelogram and angle b=80 find remaining angles

Answer 1

in a parraleogram opp angles are equal 
then ∠a=∠c ⇒80°
also ab║cd then ∠a+∠d=180°    (cointerior angles of a ║gm)
then ∠d=180-80⇒100°
also ∠d=∠b ⇒100°

:)hope this ans would help u

Answer 2

in abcd, b = 80 so a which is adjacent angle = 180-80 = 100
c which is opposite = 80 and and d which is opposite to a = 100 since in parallelograms opposite angles are equal and adjacent angles sum up to 180.

Hope this helps you.