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bonjour
C = -9x+7-12x² +6x-15
= - 12 x² - 3 x - 8
D = 13x - 18+ 6x²+21-8x
= 6 x² + 5 x + 3
E = 17x² + 4x-2+6x²-11x
= 23 x² - 7 x - 2
F = 42-16x² + 4x-37 + 3x²
= - 13 x² + 4 x + 5
bonjour
C = -9x+7-12x² +6x-15
= - 12 x² - 3 x - 8
D = 13x - 18+ 6x²+21-8x
= 6 x² + 5 x + 3
E = 17x² + 4x-2+6x²-11x
= 23 x² - 7 x - 2
F = 42-16x² + 4x-37 + 3x²
= - 13 x² + 4 x + 5