The lines a and b are parallel . Find a.

Based on the corresponding angles theorem, a = 30°.
Two angles that correspond to each other are congruent based on the corresponding angles theorem.
Thus:
5x + x = 180° (linear pair)
6x = 180
x = 180/6
x = 30
Therefore:
x = a (corresponding angles)
a = 30°
Therefore, based on the corresponding angles theorem, a = 30°.
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