Respostas

2014-08-24T19:20:12-03:00
12-5 +(3x+6).(-7)=70
7- 21x- 42= 70
-21x= 70+35
21x= - 105
x= -105/21
x= -5

2014-08-24T19:26:20-03:00
12 + ( 3x + 6 ) . ( - 7 ) - 5 = 70

- 21x = 70 + 35

- 21x = 105

x = 105/-21

x = - 5

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