Really need some help with a simple math problem

Answer:
C. 140
Step-by-step explanation:
In a parallelogram, opposite angles are congruent (equal), and consecutive angles are supplementary (add up to 180).
12x + 104 + x + 37 = 180
13x + 141 = 180
13x = 39
x = 3
Plug value of x into the x in Angle A.
12 (3) + 104
36 + 104
140
I hope this helps.