Răspuns:
1.
a) (+7)+(-7)=+7-7=0.
b)(-7)+(+4)=-7+4=-3
c)(+15)+(-10)=15-10=5
d)(-20)+(+10)=-20+10=-10
2.
a)(-10)+(+13)+(-16)+(+19)=-10+13-16+19=+6
b)(+21)+(-22)+(-23)+(+24)=21-22-23+24=0
3.
c)-3+|-4+8|+|-3+5|=-3+4+2=9
d)-25+|-12+70-8|=-25+50=+25.
Sper că te-am ajutat!
