Explanation:
First you show that the triangles are congruent.
Then you show that the segments are congruent by CPCTC (Corresponding parts of congruent triangles are congruent.)
Given:
Segment KM is congruent to segment JM
<L is congruent to <H
We now have 1 pair of sides and 1 pair of angles that are congruent.
Angles KML and JMH are vertical angles, so they are congruent.
Now we have 2 pairs of congruent angles and 1 pair of not included congruent sides.
By AAS, triangle KML is congruent to triangle JMH.
By CPCTC, segment KL is congruent to segment HJ.