Answer:
x = 7
Explanation:
Figure ABCD is a parallelogram
So sides AD and BC will be parallel and their length will be same.
[Since opposite sides of parallelogram are equal in length]
So mAD = mBC
(5x + 3) = 38
5x = 38 - 3 = 35
x =

x = 7
Therefore, x = 7 will be the answer.