5. Efectuați:
a)- 2 - 7 - 9 + 1 + 6 - 8 + 4 + 3 + 4 + 2 + 3 - 9 + 5:
b) + 6 - 8 + 2-4 + 9 + 2 + 4 + 2 - 5 - 8 - 1 + 7 + 3:
c) + 8 - 4 - 9 + 7-1-2-4-5 + 7 - 3 + 2 + 6 + 1;
d) + 8 + 5 - 4 - 7-6-9-2 + 3 +9 - 1 + 2 + 3 + 4;
e) - 6 + 2 - 9 + 7 + 2 + 3 + 4 + 8 + 3 - 9 - 4 + 1 - 5
f) + 8 + 2 - 3 - 6 + 1 + 3 + 4 + 2 - 8- 5 + 9-7-2​

Răspuns :

Salut!

Efectuati:

a)-2- 7- 9+ 1+ 6- 8+ 4+3+4+2+3-9+5

=-7-10+(-2)+7+6+5-14

=-17+5+11-14

=-12+(-3)

=-15

b)+6-8+2-4+9+2+4+2-5-8-1+7+3

=2+(-2)+11+5+(-3)-7+10

=0+16+(-10)+0

=16+(10)

=6

c)+ 8 - 4 - 9 + 7-1-2-4-5 + 7 - 3 + 2 + 6 + 1

=4-16-(-1)-(-1)-12-5+7

=-12-0-7+7

=-12-14

=-26

d)+ 8 + 5 - 4 - 7- 6- 9- 2 + 3 +9 - 1 + 2 + 3 + 4

=13-(-3)-(-3)-7+12-3+7

=16-(-10)+9+7

=26+16

=42

e)- 6 + 2 - 9 + 7 + 2 + 3 + 4 + 8 + 3 - 9 - 4 + 1 - 5

=-4+(-7)+9+7+11-5+(-4)

=-11+15+6+(-4)

=4+2

=6

f)+ 8 + 2 - 3 - 6 + 1 + 3 + 4 + 2 - 8- 5 + 9- 7- 2

=10-(-3)+4+6-3+2-2

=13+10-5-2

=23-3

=20

Sper ca te-am ajutat!