=1/2(3x-2y)-1/2(3x+2y)-3x/(3x+2y)(3x-2y)=(3x+2y)/2(3x+2y)(3x-2y) -(3x-2y)/2(3x+2y)(3x-2y)-6x/2(3x+2y)(3x-2y)=(3x+2y-3x+2y-6x)/2(3x+2y)(3x-2y)=-2(3x-2y)/2(3x+2y)(3x-2y)=-1/(3x+2y)