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Section 5-8 The Law of Cosines. A b c C a B. Solve ∆ABC if A= 120⁰, b=9, c=5. =12.3. =39.3⁰. =12.3. Solve ∆ABC if A= 105⁰, b=12, c=9. A
E N D
A b c C a B
=39.3⁰ =12.3
Solve ∆ABC ifA= 105⁰, b=12, c=9 A 105⁰ 12 9 C a B
a2 = b2 + c2 - 2bccosALaw of Cosines a2 = 122 + 92 - 2(12)(9) cos 105° a2= 280.9049137 a= 16.76021819 So, a= 16.8. B = 43.6°. C = 180° - (105° + 43.6°) C = 31.4°
B = 43.6°. C = 180° - (105° + 43.6°) C = 31.4°
Solve ∆ABC ifA= 105⁰, b=12, c=9 A 105⁰ 12 9 C a B
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