作业帮求二元二次方程组解（要有过程,急,）1.3x2-2xy-y2=0(x-y)2-3(x-y)-18=02.x2+2xy+y2=4(x-y)2+5x-5y=6
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求二元二次方程组解（要有过程,急,）1.3x2-2xy-y2=0(x-y)2-3(x-y)-18=02.x2+2xy+y2=4(x-y)2+5x-5y=6
求二元二次方程组解（要有过程,急,）
1.3x2-2xy-y2=0
(x-y)2-3(x-y)-18=0
2.x2+2xy+y2=4
(x-y)2+5x-5y=6
求二元二次方程组解（要有过程,急,）1.3x2-2xy-y2=0(x-y)2-3(x-y)-18=02.x2+2xy+y2=4(x-y)2+5x-5y=6
1.
(x-y)^2-3(x-y)-18=0
(x-y+3)(x-y-6)=0
x=y-3或x=y+6
将x=y-3代入方程3x^2-2xy-y^2=0并整理得：-12y+27=0、y=9/4、x=-3/4.
将x=y+6代入方程3x^2-2xy-y^2=0并整理得：24y+108=0、y=-9/2、x=3/2.
方程组的解为：{x=-3/4、y=9/4}、{x=3/2、y=-9/2}.
2.
(x-y)^2+5x-5y=6
(x-y)^2+5(x-y)-6=0
(x-y+6)(x-y-1)=0
x=y-6或x=y+1
将x=y-6代入方程x^2+2xy+y^2=4并整理得：y^2-6y+8=0、y=2或y=4、x=4或x=2.
将x=y+1代入方程x^2+2xy+y^2=4并整理得：4y^2+4y-3=0、y=1/2或y=-3/2、x=3/2或x=-1/2.
方程组的解为：{x=4、y=2}、{x=2、y=4}、{x=3/2、y=1/2}、{x=-1/2、y=-3/2}.
1.(x-y)(3x+y)=0
(x-y+3)(x-y-6)=0 然后分成4个方程组求解
2.（x+y)^2=4
(x-y-1)(x-y+6)=0 分成4个方程组求解哪四个1.x-y=0 x-y=0 3x+y=0 3x+y=0 x-y+3=0 x-y-6=0 x-y+3=0 x-y-...
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1.(x-y)(3x+y)=0
(x-y+3)(x-y-6)=0 然后分成4个方程组求解
2.（x+y)^2=4
(x-y-1)(x-y+6)=0 分成4个方程组求解
收起
你把y先看成1，变成1元2次来做，然后算出x，再算y