Respostas

2014-08-21T16:55:37-03:00
9x+5=4x
9x-4x=5
5x=5
x=5/5
x=1

x+9x+5=-15
10x=-15-5
10x=-20
x=-20/10
x=-2
2014-08-21T16:56:12-03:00
Dessa forma,

9x + 5 = 4x  é o mesmo que:

5x=-5, assim x=-1

x+9x+5=-15
10x=-20, x=-2