Respostas

2013-10-14T19:39:33-03:00
2
-7
2
4
30
-30

2=-7=2=4=30=-30
1 1 1
2013-10-14T19:42:19-03:00
+2 =-13 =10 -7=4 20-10=10 -50+20-30
1 1 1
e gual questão essa
(-4)+(+6)=(-10)-(-3)=(+6)-(+4)=(11)+(-7)=(+20)-(-10)=(-50)+(+20)=
-10-(-3) = -10+3 = -7
+6 - 4 = 2
20-(-10) = 20 + 10 = 30