Răspuns:
mas.∡A=66°
mas.∡B=33°
mas.∡C=81°
Explicație pas cu pas:
mas.∡A+mas.∡B+mas.∡C= 180°
mas.∡A=2·mas.∡B
mas.∡C-mas.∡B=48° ⇒mas.∡C=48°+mas.∡B Inlocuim aceste relatii in prima ecuatie mas.∡A+mas.∡B+mas.∡C= 180° ⇒2·mas.∡B+mas.∡B+48°+mas.∡B=180° ⇒4·mas.∡B=180°-48° ⇒4·mas.∡B=132° ⇒mas.∡B=33°
mas.∡A=2·mas.∡B ⇒mas.∡A=2·33° ⇒mas.∡A=66° ⇒mas.∡C=48°+mas.∡B ⇒mas.∡C=48°+33° ⇒mas.∡C=81°
Proba: mas.∡A+mas.∡B+mas.∡C= 66°+33°+81°=180°
