
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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
Answer:
you can get 12 gallons on gas
Step-by-step explanation:
x/30=1/2.42
step 1) cross multiply
x * 2.42 = 1 * 30
2.42x=30
step 2) divide both sides by 2.42
2.42x/2.42 = 30/2.42
= 12.396694
round to the nearest gallon
≈12 gallons
Answer:
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Step-by-step explanation:
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Apply formula:
and

We get:







Hence final answer is
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