Respuestas

2013-10-31T15:30:23+01:00

-3.x+12-4=-9.x+2  

9x -3x = 2 + 4 -12

6x = -6

x = -6 / 6 = -1




2013-10-31T16:04:29+01:00
-3x+12-4=-9x+2
-3x+9x=-12+4+2
+6x=-8+2
+6x=-6
x=-6 / +6
x=-1