Answer:
118.6°
Explanation:
You want the value of the obtuse angle marked x in the triangle with sides 20, 23, and 37.
Law of Cosines
In the given triangle, the relevant formulation of the law of cosines is ...
b² = a² +c² -2ac·cos(B)
Solving for angle B, we get ...
B = arccos((a² +c² -b²)/(2ac))
B = arccos((20² +23² -37²)/(2·20·23)) ≈ 118.6°
The value of x is about 118.6°.