Respostas

2014-08-14T21:57:34-03:00
A ) 5x - 4 = 6x + 8
5x - 6x = 8 + 4
- x = 12 . ( - 1 )
x = - 12

b ) 7x - 2 = - 4x + 5
7x + 4x = 5 + 2
11x = 7
x = 7/11 ou 0,63

c ) 2x + 10 - 10 = 100 - 10
2x = 100 - 10 - 10 + 10
2x = 90
x = 90/2
x = 45

d ) 2 . ( x + x - 28 ) - 200 = 0
2x + 2x - 56 - 200 = 0
4x = 56 + 200
4x = 256
x = 256/4
x = 64