Respostas

2014-03-27T18:24:20-03:00
Calcule
a) -6 + 10 - 4
= -10 +10
=0
b) 15 - 7 - 13 + 1
=-20 +16
=-4
c) -3 + 4 - 6 - 4 + 3
=-13 +7
=-6