Respostas

2013-08-20T11:18:31-03:00
3.(x+7)-3=2.(4-x)
3x+21-3=8-2x
3x+2x=8+3-21
5x=-10
x=-10/5
x=-2

5.(x+1)=4.(2-x)
5x+5=8-4x
5x+4x=8-5
9x=3
x=3/9, simplificando: x=1/3 ou x=0,333...