Răspuns :
m (AOB)=2x°+50°
m (BOC)=6x°
m (AOC)=x°+40°
m (AOB)+m (BOC)+m (AOC)=360°
2x°+50°+6x° +x°+40°=360°
9x°=360°-90°
9x°=270°
x°=30°
m (AOB)=2x°+50°=2×30°+50°=60°+50°=110°
m (BOC)=6x° =6×30°=180°
m (AOC)=x°+40°=30°+40°=90°
m (MON=m(AOB)/2+m (AOC)/2=110°/2+90°/2=180°/2=90°
m (BOC)=6x°
m (AOC)=x°+40°
m (AOB)+m (BOC)+m (AOC)=360°
2x°+50°+6x° +x°+40°=360°
9x°=360°-90°
9x°=270°
x°=30°
m (AOB)=2x°+50°=2×30°+50°=60°+50°=110°
m (BOC)=6x° =6×30°=180°
m (AOC)=x°+40°=30°+40°=90°
m (MON=m(AOB)/2+m (AOC)/2=110°/2+90°/2=180°/2=90°
2x+50+6x+x+40=360
9x+90=360/-90
9x=270/:9
x=30
m(AOB)=110
m(BOC)=180
m(COA)=70
m(MON)=70:2+110:2=25+55=90=> unghi drept
9x+90=360/-90
9x=270/:9
x=30
m(AOB)=110
m(BOC)=180
m(COA)=70
m(MON)=70:2+110:2=25+55=90=> unghi drept