Question

Tìm x,y thuộc Z

y.(2.x + 1 ) = x+7

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Answer 1

y.(2x +1)= x+y
<=> 2xy +y = x+y
<=> 2xy+y-x-y= 0
<=> 2xy- y= 0
<=> 2y( x-1)= 0

<=> y=0 hoặc x-1=0 (x=1)

Answer 2

Đề sai nhé

\(y\left(2x+1\right)=x+y\)

\(\Rightarrow2xy+x=x+y\)

\(\Rightarrow2xy=y\)

\(\Rightarrow2xy-y=0\)

\(\Rightarrow2x\left(y-1\right)=0\)

\(\Rightarrow\left\{{}\begin{matrix}2x=0\Rightarrow x=0\\y-1=0\Rightarrow y=1\end{matrix}\right.\)