Bonjour,
Développer puis réduire.
A = 5(10x + 8)
A = 50x + 40
B = 9x(6 - 6x)
B = 54x - 54x²
B = -54x² + 54x
C = 3(4x + 7) + 4(2x - 9)
C= 12x + 21 + 8x - 36
C = 20x - 15
D = 7x(2x - 5)
D = 14x² - 35x
E = (2x + 3)(5x - 8) - (2x - 4)(5x - 1)
E = (10x² - 16x + 15x - 24) - (10x² - 2x - 20x + 4)
E = 10x² - x - 24 - 10x² + 22x - 4
E = 21x - 28
F = (y - 3)(y + 3)
F = y² + 3y - 3y - 9
F = y² - 9
G = (x + 2)-(3x - 5)
G = x + 2 - 3x + 5
G = -2x + 7
Bonne journée.