1)suma unghiurilor suplementare=180 grade
suma unghiurilor complementare =90 grade
2) a-b= 8 grade 20 min
a+b=90 grade
2a= 98 grade 20 min
a= 49 grade 10 min
b=40 grade 50min
3) a-b=37
a+b=180
2a=180+37
a=217/2 = 108 grade 30 min
b= 71 grade 30 min
4) a/b=7/5
a+b=180
a+5a/7=180
7a+5a=180x7=1260
12a=1260
a=1260/12=105 grade
b=180-105=75 grade
5) a= 4b
a+b=90
4b+b=90
5b=90
b=18 grade
a=90-18=72 grade