Respostas

2014-09-02T12:33:48-03:00
-5+8-7+9-3=2

sinais iguais VC soma, sinais diferentes VC subtrai :)
2014-09-02T13:34:06-03:00
(-5)-(-8)+(-7)-(-9)+(-3)
-5+8-7+9-3
-15+16=1