Răspuns:
Le rezolv in coloana
7-9=-2
7-0=7
-12+1=-11
0+9=9
-5-8=-13
-6-3=-9
5+9=14
1+1=2
4-7=-3
-6-31=-37
-19+21=2
3-3=0
0-5=-5
-7+10=3
-6-9=-15
-7-9=-16
-9-4=-13
2+6=8
10+2=12
-8-2=-10
-14+12=-2
14+15=29
