Answer:
= 27°
Step-by-step explanation:
Given: ABCD is a Quadrilateral and AB is parallel to CD and
=27 degree
We have to find out:

since, AB is parallel to CD , and according to the properties of parallel lines If two parallel lines are cut by a transversal line then the alternative interior angles made by that transerversal are always equal.
here BD makes the transversal line for parallel lines AB and CD. and
and
are interior angles of lines CD and AB respectively. And these angle are alternative to each other.
Thus they must have the equal values. This implies if
= 27° then
= 27°