(3-x)/(1-x)-(5-x)/(7-x)=1-(x²-2)/(x²-8x+7)(x-3)/(x-1)-(x-5)/(x-7)=(x²-8x+7-(x²-2))/((x-1)(x-7))((x-3)(x-7)-(x-5)(x-1))/((x-1)(x-7))=(9-8x)/((x-1)(x-7))x²-10x+21-x²+6x-5=9...