For this case we have to:
AB is parallel to DC
AD is parallel BC
So the angles DAB and DCB are equal. And the angles CDA and ABC are the same too (55 each)
The sum of the internal angles of a parallelogram is 360 degrees.
[tex]55 + 55 + 2DAB = 360\\110 + 2DAB = 360\\DAB = \frac {360-110} {2}\\DAB = 125[/tex]
Answer:
125
