Respostas

2014-03-11T16:53:48-03:00
A) 3x+1=0
3x = -1
x = -1/3

b) -5x-15=10
-5x = 15
x = 15/-5
x = -3

c) 8x+12=-18
8x = -18-12
8x = -30
x = -30/8 = -15/4