Answer:
D. 8.54147
Step-by-step explanation:
Side a = 7
Side b = 6
Side c = 12.71762
Angle ∠A = 12.937° = 12°56'12" = 0.22579 rad
Angle ∠B = 11.063° = 11°3'48" = 0.19309 rad
Angle ∠C = 156° = 2.72271 rad = 13/15π
C=156°B=11.063°A=12.937°b=6a=7c=12.718
Area = 8.54147
