Oblicz
1-(-2)
2+(-8)
-3-7
20+(-6)
30-12
-15+7
-6-7
źródło:
1-(-2)=1+2=3
2+(-8)=2-8=-6
-3-7=-10
20+(-6)=20-6=14
30-12=18
-15+7=-8
-6-7=-13