Câu hỏi của Trương Thị Kiều Oanh

Question

xy+x+y+1=0

xy-x-y=0

xy-x-y-1=0

xy-x-y+1=0

xy+2x+y+11=0

Mashiro Shiina · Accepted Answer

Hướng dẫn thôi nhé:

Lời giải:

a)$xy+x+y+1=0$

$\Rightarrow x\left(y+1\right)+1\left(y+1\right)=0$

$\Rightarrow\left(x+1\right)\left(y+1\right)=0$

b)$xy-x-y=0$

$\Rightarrow xy-x-y+1=1$

$\Rightarrow x\left(y-1\right)-1\left(y-1\right)=1$

$\Rightarrow\left(x-1\right)\left(y-1\right)=1$

c)$xy-x-y-1=0$

$\Rightarrow xy-x-y+1=2$

$\Rightarrow x\left(y-1\right)-1\left(y-1\right)=2$

$\Rightarrow\left(x-1\right)\left(y-1\right)=2$

d) $xy-x-y+1=0$

$\Rightarrow x\left(y-1\right)-1\left(y-1\right)=0$

$\Rightarrow\left(x-1\right)\left(y-1\right)=0$

e)$xy+2x+y+11=0$

$\Rightarrow xy+2x+y+2=-9$

$\Rightarrow x\left(y+2\right)+1\left(y+2\right)=-9$

$\Rightarrow\left(x+1\right)\left(y+2\right)=-9$Câu trả lời: Hướng dẫn thôi nhé: