Respostas

2013-12-03T14:06:18-02:00
12 - 3 = 9
3/9 = (x - 1)/ 12
9.(x - 1) = 3 . 12
x - 1 = 36/9
x - 1 = 4
x = 4 + 1
x = 5
8 4 8