x-7/x-9+x-3/x-5=x-4/x-6+x-6/x-8
x-7/x-9-x-4/x-6=x-6/x-8-x-3/x-5
通分
[(x-7)(x-6)-(x-4)(x-9)]/[(x-9)(x-6)]=[(x-6)(x-5)-(x-3)(x-8)]/[(x-5)(x-8)]
(42-36)/[(x-9)(x-6)]=(30-24)/[(x-5)(x-8)]
得(x-9)(x-6)=(x-5)(x-8)
-15x+54=-13x+40
2x=14
x=7

x=7
左边=-3
右边=-3