R
rinnegan_97


giải hệ sau:
[TEX](x^2+xy)^2=2x+9[/TEX]
[TEX]2(x^2+xy)=x^2+6x+9[/TEX]
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[TEX](x^2+xy)^2=2x+9[/TEX]
[TEX]2(x^2+xy)=x^2+6x+9[/TEX]
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