Bonjour,
D = 36 + 24x + 4x²
D = 4 (x + 3)²
E = (3x - 6)² - (x + 7) (3x - 6)
E = (3x - 6) [(3x - 6) - (x + 7)]
E = (3x - 6) (3x - 6 - x - 7)
E = (3x - 6) (2x - 13)
E = 3 (x - 2) (2x - 13)
F = 64x² - 25
F = (8x - 5) (8x + 5).
