Question

1. $\triangle jkn cong \triangle$ lkm by sas

Explanation:

1. Identify congruent sides: The tick marks show $JK \cong LK$ and $JN \cong LM$.
2. Identify congruent angles: Vertical angles $\angle JKN \cong \angle LKM$.
3. Match the SAS congruence rule: The congruent angle is between the two pairs of congruent sides, so the triangles are congruent by SAS, with the corresponding triangle being $\triangle LKM$.

Answer:

The completed statement is $\triangle JKN \cong \triangle LKM$ by SAS.