Respostas

2014-04-12T12:23:33-03:00


2²-x²- 16+4x-4x-x²=
4-x²-16-x²=

-2x²-12= 0

-2x²=12

x²= 12/-2=

x²= -6
2014-04-12T12:36:15-03:00


4 - 4x +  x^{2} - 16 - 4x + 4x - x

-4x = 20 .(-1)

4x = -20

x = -5