解方程：x-2分之x+x-7分之x-9=x-1分之x+1+x-6分之x-8

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再问： 没有括号
再答： 是这样吗？ x/(x-2)+x/(x-7)-9=x/(x-1)+1+x/(x-6)-8
再问： 是：x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6)
再答： x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6) (x-2+2)/(x-2)+(x-7-2)/(x-7)=(x-1+2)/(x-1)+(x-6-2)/(x-6) 1+2/(x-2)+1-2/(x-7)=1+2/(x-1)+1-2/(x-6) 1/(x-2)+1-1/(x-7)=1/(x-1)-1/(x-6) [x-7-(x-2)]/[(x-1)(x-2)]=[x-6-(x-1)][(x-6)(x-7)] -5/[(x-1)(x-2)]=-5[(x-6)(x-7)] (x-1)(x-2)=(x-6)(x-7) x^2-3x+2=x^2-13x+42 10x=40 x=4 经验证，x=4不是增根