180°-40°=140° - A+B
A+B=x+5°+x+15°
A+B=2x+20°
2x+20°=140°
2x=140°-20°
2x=120°
x=120°:2
x=60°
A=60°+5°
A=65°
B=60°+15°
B=75°
180°-40°=140° - A+B
A+B=x+5°+x+15°
A+B=2x+20°
2x+20°=140°
2x=140°-20°
2x=120°
x=120°:2
x=60°
A=60°+5°
A=65°
B=60°+15°
B=75°