Answer:
The reasons in order:
Given
Corresp. Ang. Post.
Corresp. Ang. Post.
Transitive
Explanation:
The first reason is "given" because they gave that information to you, which means it is true. Angle 1 and angle 9 are corresponding angles (if you slid line L over to line M, the angles would match up). According to the corresponding angles postulate, this makes them congruent. This is also the case with angles 9 and 13 (if you slid line A down to line B, the angles would match up). So, according to the transitive property of equality, since 1 is congruent to 9 and 9 is congruent to 13, this means 1 is congruent to 13. (basically, 1 = 9, 9 = 13, so 1 = 13)
hope this helped.