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9² = 12² + 15² - 2 (12) (15) cos (B)
81 = 144 + 225 - 360 cos(B)
81 = 369 - 360 cos (B)
360 cos (B) = 369 - 81
360 cos (B) = 288
cos (B) = 0.8
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Answer: Cosine B = 0.8
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12² = 15² + 9² - 2 (15)(9) cos (A)
144 = 225 + 81 - 270 Cos A
144 = 306 - 270 Cos A
270 Cos A = 162
Cos A = 3/5 or 0.6
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Answer: Cosine Angle A = 3/5
I think the answer is 5×500
1st term = -10
2nd term = -6
3rd term = -2
4th term = 2
5th term = 6
6th term = 10
7th term = 14
The reason how I got 14 for the 7th term is because, i added 4 to each term.
Hope this helps!
Answer:
its B, 90
Step-by-step explanation:
thats a right triangle so the r angle is 90