Respostas

2014-07-23T02:26:59-03:00
(2x + 3)(x - 5) = 4x + 9
2x^2 - 10x + 3x - 15 = 4x + 9
2x^2 - 10x + 3x - 15 - 4x + 9 = 0
2x^2 - 10x - 4x + 3x - 15 + 9 = 0
2x^2 - 11x - 6 = 0

(2x - 3) (2x) = 6x - 3
4x^2 - 6x - 6x + 3 = 0
4x^2 - 12x + 3 = 0