bonjour
A = x² + 2x = x( x + 2 )
B = 7x ( x- 4) - (x-4)² = (x-4)(7x-x+4) = (x-4)(6x+4) = ( x - 4 ) 2(3x+2)
C = (x+1)(2x+5)-(x+1)(3x+4) = (x+1)(2x+5-3x-4)= (x+1)(1-x)
D = 9x² + 3 x = 3x( 3x +1 )
bonne continuation
