Răspuns:
Explicație pas cu pas:
<1+<2=180
notez<2=x
3/5*x+x=180
3x/5+5x/5=8x/5=180
8x=5*180
x=180*5/8=900/8=225/2=224grade 60 min/2
<2=112 grade 30min
1=180-112grade 30 min=179 grade 60min- 112 grade 30min
<1=67 grd 30min
b) notez <1=x
2x/3+x=180
2x/3+3x/3=180
5x/3=180
5x=540
x=108 grade
<1=108 grade
<2=180-108
<2=72 grade