Răspuns:
∡A=120°
∡B=140°
∡C=100°
Explicație pas cu pas:
AB=∡C
BC=∡A
CA=∡B
∡A+∡B+∡C=360°
[tex]\frac{AB}{5} = \frac{BC}{6} = \frac{CA}{7} = K[/tex]
AB=5K
BC=6K
CA=7K
5K+6K+7K=360
18K=360 => K=360/18 => K=20
AB=5*20=100° => ∡C=100°
BC=6*20=120° => ∡A=120°
CA=7*20=140° => ∡B=140°
