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问题: 初二数学题

解方程(写清步骤)
1.x/x-6=x-2/x-3
2.2x/2x+5+5/5x-2=1
3.x-1/x-2=1/x-2

解答:

解方程(写清步骤)
1.(x)/(x-6)=(x-2)/(x-3)
===> x*(x-3)=(x-6)*(x-2)
===> x^2-3x=x^2-8x+12
===> 5x=12
===> x=12/5

2.(2x)/(2x+5)+(5)/(5x-2)=1
===> (2x)/(2x+5)=1-(5)/(5x-2)
===> (2x)/(2x+5)=(5x-7)/(5x-2)
===> 2x*(5x-2)=(5x-7)(2x+5)
===> 10x^2-4x=10x^2+11x-35
===> 15x=35
===> x=7/3

3.(x-1)/(x-2)=(1)/(x-2)
===> (x-1)*(x-2)=1*(x-2)
===> (x-2)*(x-2)=0
===> (x-2)^2=0
===> x=2
但是,x=2时,等式无意义
===> 此题无解