Answer:
38 degrees
Step-by-step explanation:
By the Law of Cosines,
5² = 3² + 7² - 2(3)(7) cos A
5² - 3² - 7² = -2(3)(7) cos A
-33 = -42 cos A
cos A = 33/42
A = arccos(33/42), which is about 38 degrees.
