Respostas

2014-06-25T15:51:17-03:00
7x + 1 - 5x = 9
7x - 5x = 9 - 1
2x = 8
x = 8 / 2 
x = 4
2014-06-25T15:55:09-03:00
7x+1-5x=9 
7x-5x=9-1
+2x=8
x=8/2
x=4