Réduire les expression: À= 3x-9x+2x-8x B=13x-x-3x C=7x-5-9x+2 D=10x-1+4-13x+9+x E=4x-3y+3x-9y-12x

A= 3x-9x+2x-8x
  = 5x - 17x
  =-12x
B=13x -x -3x
  = 13x - 4x
  = 9x
C=7x-5-9x+2
  =-2x-3
D= 10x-1+4-13x+9+x
  = 11x-13x+12
  = -2x+12 = 2(6-x)
 E=4x-3y+3x-9y-12x
   =7x-12x-12y
   =-5x-12y