Respostas

2014-04-02T14:45:17-03:00
X=0,777... x (10) 10x=7,777... - x=0,777... 9x=7 x=7/9 x=1,222... x (10) 10x=12,222.... - x= 1,222... 9x=11 x=11/9 7/9 + 11/9 = 18/9