Respostas

2013-09-11T22:10:11-03:00
7x-[5x+3-2x-1-10]= +x-3
7x-[3x-8]=x-3
7x-3x+8-x+3=0
3x+11=0
3x=-11
x= -11/3
x= -3,6666...
2 3 2
2013-09-11T22:22:03-03:00
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7X - [5X + 3 - (2X +1) -10] = -(X + 3)
7X - [5X + 3 - 2X - 1 - 10] = - X - 3
7X -5X - 3 + 2X +1 + 10 = - X - 3 
>> ARRUMANDO A EXPRESSÃO<<
7X - 5X + 2X + X = - 3 + 3 - 1 - 10
5X = -11
X = -11/5

=0
1 5 1