Question

$\triangle kjl \cong \triangle stu$. what is $us$? \boxed{} millimeters

Explanation:

Step1: Find missing angle in △KJL

Sum of angles in triangle is $180^\circ$.
$\angle J = 180^\circ - 59^\circ - 79^\circ = 42^\circ$

Step2: Match congruent triangle sides

$\triangle KJL \cong \triangle STU$, so $\angle J \cong \angle T$ (both $42^\circ$). Corresponding sides: $US$ corresponds to $JK$.

Answer:

50 millimeters