find c! please explain the steps and help me find the answer.
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Answer:
34.78
Step-by-step explanation:
using cosine rule
AB^2 = CB^2 + AC^2 -2(CB × AC × COS C)
18^2 = 17^2 + 27^2 -2(27×17×COS C)
324= 289+729- 918COSC
324-289-789= -918COSC
-754= -918COSC
COS C = 754/918
COS C = 0.82135076253
C= arccos(0.82135076253)
C= 34.78(2 dp)