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Answer:
c = √(42² +35² -2·42·35·cos(120°))
Step-by-step explanation:
The third side can be found using the Law of Cosines. It will tell you ...
c² = a² +b² -2ab·cos(C)
where C is the angle opposite the third side (c). For the given side lengths, then the third side can be found from ...
c = √(42² +35² -2·42·35·cos(120°))
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Additional comment
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