bonsoir
4 x² - 49 = ( 2 x - 7 ) ( 2 x +7 )
2 x² - 5 x + 3 = 2 ( x - 1 ) ( x - 3 /2 )
5 x² - 7 x = x ( 5 x - 7 )
x² - 5 x - 14 = ( x - 7 ) ( x + 2 )
