Réponse:
les expressions A,Bet C sont égaux
car
[tex]a = - 3(4 - 5x) - {10x}^{2} + 8x \\ = - 3 \times 4 + 3 \times 5x - {10x}^{2} + 8x \\ = - 12 + 15x - {10x}^{2} + 8x \\ = - {10x}^{2} + 23x - 12[/tex]
[tex]b = (2x - 3)(4 - 5x) \\ = 2x \times 4 - 2x \times 5x - 3 \times 4 + 3 \times 5x \\ = 8x - {10x}^{2} - 12 + 15x \\ = - {10x}^{2} + 23x - 12[/tex]
[tex]c = 2x(4 - 5x) + 15x - 12 \\ = 2x \times 4 - 2x \times 5x + 15x - 12 \\ = 8x - {10x}^{2} + 15x - 12 \\ = - {10x}^{2} + 23x - 12[/tex]
