Caranya juga ya. Pls ok dapat poin loh 15

x= 80°+4x° =180°
4x° =180°-80°
4x° =100°
x° = 100/4 = 25°
y= (y+3)° +4x° = 180°
y+3 + 4(25) = 180
y+3+100= 180
103y =180
y= 180-103 = 77°
z= 4z-20+80 =180
4z = 180+20-80
4z = 120
z = 120/4 =30°

semoga benar:)