=(x-1)/(x+1)(x+2)-6/(x+1)(x-2)-(x-10)/(x+2)(x-2)
=(x^2-3x+2)/(x+1)(x+2)(x-2)-(6x+12)/(x+1)(x+2)(x-2)-(x^2-9x-10)/(x+1)(x+2)(x-2)
=0