Respostas

2013-12-16T17:59:21-02:00
5- A) (3+x)² = 9 + 2.3.x + x² = 9+6x+x²

B) (2x+5)² = (2x)² + 2. 2. x. 5 - 5²= 4x²+20x-25

C) (x+3). (x-3) = x² - 3² = x² - 9

6- Resposta letra A