Answer:
71 degrees
Step-by-step explanation:
Let's close the top part of the picture to make a parallelogram.
A parallelogram's four angles at each corner MUST be equal to 360 degrees.
Another property of a parallelogram is the opposite angles are congruent, meaning they're equal.
So, using these properties, we can now solve for a.
[tex]360=a+a+109+109\\360=2a+218\\142=2a\\71=a[/tex]
