When a transversal cuts two parallel lines, the pairs of exterior angles that alternate sides of the transversal are called "Alternate exterior angles". The measures of these angles are equal (they are congruent).
In this case, you can identify in the picture that the following angles are "Alternate exterior angles":
Therefore, since their measures are equal (they are congruent), you can write the following equation which can be used to solve for "x":
The answer is the Second option.