voila il y en a 7 A= (4-x)(5+3x) + 2x - 8 B= (x-2)²- (7x+6)² C= (x-2)(5x+2) + (x-2) D= (5x-1)² - 81 E= 4-x² + (6+x)(2-x) F= (x-1)² - (5-x) (x-1) G= 16x² - 24x +

A= (4-x)(5+3x) + 2x - 8
= (4 X 5 ) + (4 X 3x) + (-x X5) + (-xX 3x) + 2x -8
= 20 + 12x -5x -3xau carré  + 2x -8
=3x au carré +9x + 12

B= (x-2)²- (7x+6)²
 = x au carré -4x + 4 -( 49x au carré + 84x + 36)
= x au carré - 4x +4 -49x au carré -84x -36
= -48x au carré - 88x - 32

C= (x-2)(5x+2) + (x-2)
= (xX5x) + (xX2) + (-2 X5x )+ (-2 X 2) + (x-2)
= 5 x au carré + 2x - 10x -4 + x - 2
= 5 x au carré - 7x  - 6

A=(4-x)(5+3x)+2x-8
A=20+12x-5x-3x.x+2x-8
A=12+9x-3x.c