Respostas

2013-06-07T15:31:33-03:00

2bx(1-a) + 2x(a-b-c) - 2x(a-c)
2bx - 2abx + 2ax - 2bx - 2cx - 2ax + 2cx
(2bx - 2bx) + (2ax - 2ax) + (2cx - 2cx) - 2abx
0 + 0 + 0 - 2abx
-2abx

6 4 6