Respostas

2014-03-22T17:32:47-03:00
0,25^x-4=0,5^-2x+4
0,5^2 . (x-4) = 0,5^-2x+4
0,5^2x - 8 = 0,5^-2x+4
2x - 8 = -2x + 4
2x + 2x = 4 + 8
4x = 12
x = 3
1 5 1