We are asked to determine whether there is enough information to prove that a is parallel to b.
From the given figure, we can see that the alternate interior angles are congruent.
Recall the alternate interior angles converse,
For the given case, lines a and b are cut by a transversal and the alternate interior angles are congruent.
So, the alternate interior angles converse is applicable.
Therefore, we have enough information to conclude that lines a and b are parallel.
"Yes, Alternate Interior Angles Converse"