Respostas

2013-08-05T13:38:38-03:00
A + 4 = 8   ---- a= 8-4--- a= 4

b-5 = -2 ----- b = +5-2---- b= 3

c-3 =3  ------ c= 3+3 ---- c = 6

d+8 =1 ------- d= -8+1----- d = -7