Answer:
34°
Explanation:
The law of cosines is good for finding angles when only sides are known. We'll use the conventional sides a, b, c, and angles A, B, C. Yes, we know the problem statement calls the smallest angle "J". We trust you can make the translation.
a² = b² +c² -2bc·cos(A) . . . . . for sides a, b, c and angle A
Solving for the angle, we get ...
A = arccos((b² +c² -a²)/(2bc))
Filling in the numbers with "a" being the shortest side, we have ...
A = arccos((13² +19² -11²)/(2·13·19)) = arccos(409/494)
A ≈ 34.113°
The smallest angle, ∠J, is about 34°.