Answer: The value of x = 9.
Explanation:
Since we have given that
∠A = (30+5x)°
∠ D = (15+10x)°
Since ABCD is a parallelogram.
In parallelogram, opposite angles are equal and sum of adjacent angle is supplementary angles.
So, ∠A + ∠D = 180° (∵ A and D are adjacent angles)

Hence, the value of x = 9.