Réponses

2013-10-13T18:40:45+02:00
A = (3x-10)(2x-7)-(8x-9)(6x-7)
   = (6x²-21x-20x+70)-(48x²-56x-54x+63)
   = 6x²-21x-20x+70-48x²+56x+54x-63
   = -42x²+69x+7
2013-10-13T18:42:10+02:00
A = (3x - 10) (2x -7) - (8x-9) (6x-7) 
=6x²-21x-20x+70-(48x²-56x-54x+63)
=6x²-21x-20x+70-48x²+56x+54x-63
= -42x²+69x+7