a || b
c = secanta
< 1 si < 2 = alterne interne => <1 = <2
masura(<1) = 47° => masura(<2) = 47°
<2 op.vf cu <7 => <2 = <7
masura(<2)=47° => masura(<7)=47°
masura(<7) + masura (<8) = 180°
47° + x° = 180°
x= 180°-47°
x=133°
Concluzie!! Unghiul 8 are 133° sau x=133°
