please help I dont understand
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Answer:
50 degrees
Step-by-step explanation:
By the Law of Cosines,
6² = 7.5² + 6.5² - 2(6.5)(7.5)cos C
6² - 7.5² - 6.5² = -2(6.5)(7.5)cos C
-62.5 = -97.5 cos C
cos C = (-62.5)/(-97.5) = 25/39
C = arccos(25/39), which is about 50°