Respostas

2014-08-12T10:25:55-03:00
A)7x - 2 = -4x + 5
7x + 4x=5 + 2
11x = 7
x= 7/11
b)
x + 8 = 28 – x
x + x= 28 - 8
2x= 20
x= 20/2
x= 10