二元一次方程的计算.(2x-3)(x-2)=392(10-2x)(8-2x)=64x^2+(x+2)^2=(x+4)^2

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二元一次方程的计算.(2x-3)(x-2)=392(10-2x)(8-2x)=64x^2+(x+2)^2=(x+4)^2
二元一次方程的计算.
(2x-3)(x-2)=392
(10-2x)(8-2x)=64
x^2+(x+2)^2=(x+4)^2

二元一次方程的计算.(2x-3)(x-2)=392(10-2x)(8-2x)=64x^2+(x+2)^2=(x+4)^2
(2x-3)(x-2)=392
2x^2-7x-386=0
x=(7-√3137)/4,x=(7+√3137)/4
(10-2x)(8-2x)=64
(x-5)(x-4)=16
x^2-9x+4=0
x^2-9x+81/4=-4+81/4
(x-9/2)^2=97/4
x-9/2=±√97/2
x=(9-√97)/2,x=(9+√97)/2
x^2+(x+2)^2=(x+4)^2
x^2+x^2+4x+4=x^2+8x+16
x^2-4x-12=0
(x+2)(x-6)=0
x=-2,x=6

原式=(x-y)/(x+3y)×[(x+3y)^2/(x+y)(x-y)]-2y/(x+y)
=(x+3y)/(x+y)-2y/(x+y)
=(x+3y-2y)/(x+y)
=(x+y)/(x+y)
=1