(x-1)(x+1) - 2(x+1)=0 => (x+1)(x-1-2) = 0 => (x+1)(x-3) = 0 x= -1 ou x = 3
4-9(x-1)²=0 => (2 - 3x+3)(2 + 3x - 3) = 0 => (5 - 3x)(3x-1) = 0 x = 5/3 ou x = 1/3
16x²- 25x=0 => x(16x - 25) = 0 => x = 0 ou x = 25/16
(5x-3)²-4(2x-3)²=0 => (5x-3 - 2(2x-3))(5x-3 + 2(2x-3)) = 0 => (5x-3-4x+6)(5x-3+4x -6) = 0
(x+3)(9x-9) = 0 => x = -3 ou x = 1
