Bonjour,
A= 8-4x +3 = -4x +11
B= 6 -8x +4 -8x = 10
C= -6x -2 -3x -9 = -9x -11
D= 30x -5 -3 -8x = 22x -8
E = 2x² +8x +x -x = x² +8x
F= -2x +x² +x² -2x -3x² +4
= -x² -4x +4
G = 3x² -x² +4x -5 -4x² +12x
= -2x² +16x -5
H= 2x² -7x +4+ 12x -8x²
= -6x² +5x +4
I = -15x²-30x +15x² -18x +6
= -48x +6
