Respostas

2014-08-19T07:40:43-03:00
X+5=3x = 3x-x=5 = 2x=5 = x=2/5

6x+10=x = 6x-x=-10 = 5x= -10 = x=-10/5 = -2

2x+x=21 = 3x=21 = 21/3 = x=7

X+6=21 = x = 21-6 = x= 15

3x-2x+3=-9 = x= -9-3 = x = -12