Bonjour
A = 4x (8x + 4) + 8 (5 - x)
A = 32x² + 16x + 40 - 8x
A = 32x² + 8x + 40
B= (x - 1) (2x + 3) + (5x + 1)²
B = 2x² + 3x - 2x - 3 + 25x² + 10x + 1
B = 2x² + 25x² + 3x + 10x - 2x - 3 + 1
B = 27x² + 11x - 2
C = (2x - 4) (6x - 7) - 3x(2x + 4)
C = 12x² - 14x - 24x + 28 - 6x² - 12x
C = 12x² - 6x² - 14x - 24x - 12x + 28
C = 6x² - 50x + 28
D = (2x + 6)² - (2x - 6)²
D = 4x² + 24x + 36 - (4x² - 24x + 36)
D = 4x² + 24x + 36 - 4x² + 24x - 36
D = 4x² - 4x² + 24x + 24x + 36 - 36
D = 48x
