Answer: Last option.
Step-by-step explanation:
Observe the figure attached.
In order to find the value of "b", you need to remember the definition of "Alternate interior angles". These are the pairs of angles located in the interior of the parallel lines and on opposite side of the transversal. They are congruent.
Based on this definition, you can conclude that the angle "b" and the angle that measures 128° are Alternate interior angles; therefore they are congruent.
This means that the value of "b" is:
