Respostas

2013-12-17T17:38:50-02:00
A) 4x + 8 = 3x + 5 <=>
<=> 4x - 3x = 5 - 8 <=>
<=> x = -3 

b) 3a - 4 = a + 1 <=>
<=> 3a - a = 1 + 4 <=>
<=> 2a = 5 <=>
<=> a = 5/2  


3 1 3
2013-12-17T17:40:52-02:00
a) 4x + 8 = 3x - 5
4x - 3x = - 5 - 8
x = - 13

b) 3a - 4 = a + 1
3a - a = 1 + 4
2a = 5
a = 5 ÷ 2
a = 2,5
4 3 4