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PLEASE HELP LAW OF COSINES

Find the measure of J, the smallest angle in a triangle with sides measuring 11, 13, and 19. Round to the nearest whole degree.

30°
34°
42°
47°

PLEASE HELP LAW OF COSINES Find the measure of J, the smallest angle in a triangle-example-1
User Rahstame
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2 Answers

3 votes

Answer:

34 degrees

Explanation:

edg quiz

User Digy
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5 votes
The Law of Cosine states
cos
C=(a^2+b^2-c^2)/2ab

so plugging in the numbers gives us

cos
J=(13^2+19^2-11^2)/2(13*19) = 409/494

We now have cosJ so plug that into your calculator and find arccos (arccos(cos(J)) = J)
arccos
(409/494)=34.11
rounding your answer will give you 34°
User Katharine
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