Chapter 3 - Parallel and Perpendicular Lines - 3-3 Proving Lines Parallel - Practice and Problem-Solving Exercises - Page 162: 35

$\angle1\cong\angle5$ $l\parallel n$

Because angles 1 and 5 are in corresponding positions relative to the angles formed when line k intersects with lines l and n, the Converse of the Corresponding Angles Theorem tells us that $l\parallel n$.