Bonjour
1)
A = 3 (4x - 2)
A = 12x - 6
B = 5 (4 + 3x)
B = 20 + 15x
C = 2x (x - 4)
C = 2x² - 8x.
2)
D = 3 + (4x - 2)
D = 3 + 4x - 2
D = 4x + 1
E = 2x - (6 + 3x)
E = 2x - 6 - 3x
E = - x - 6
F = (3x + 5) - (2x - 1)
F = 3x + 5 - 2x + 1
F = x + 6
G = - (x + 7) + (4x - 2)
G = - x - 7 + 4x - 2
G = 3x - 9
3)
H = - 3 (8x - 4)
H = - 24x + 12
I = 2 (x + 9) - (4x - 1)
I = 2x + 18 - 4x + 1
I = - 2x + 19
J = (5x + 4) - (6x - 8) + 4 (2 - 3x)
J = 5x + 4 - 6x + 8 + 8 - 12x
J = 5x - 6x - 12x + 4 + 8 + 8
J = - 13x + 20.