Answer:
49degrees
Explanation:
Using the cosine rule
u² = v²+w²-2vwcosU
Substitute the given values
51² = 61²+62²-2(61)(62)cosU
2601 = 3721+3844-7564 cosU
2601 = 7565-7564cosU
-7564cosU = 2601-7565
-7564cosU = -4964
CosU =-4964/-7564
CosU = 0.6563
U = arccos(0.6563)
U = 49degrees(to nearest degree)