\(\hept{\begin{cases}\frac{2}{x-y}+\sqrt{y+1}=4\\\frac{1}{x-y}-3\sqrt{y+1}=-5\end{cases}}\) 

ĐKXĐ : \(x\ne y,y\ge-1\)

Ta có : \(3.\left(\frac{2}{x-y}+\sqrt{y+1}\right)=12\)

Cộng với phương trình ( 2 ) ta có :

\(\frac{7}{x-y}=7\Rightarrow\frac{1}{x-y}=1\Rightarrow x=y=1\)

Thay vào hệ phương trình ta có :

\(\hept{\begin{cases}2+\sqrt{x}=4\\1-3.\sqrt{x}=-5\end{cases}}\)

Cộng pt 1 và pt 2 ta có : \(3-2.\sqrt{x}=-1\)\(\Rightarrow2.\sqrt{x}=4\)\(\Rightarrow\sqrt{x}=2\Rightarrow x=4\)

= > y = 3

-19684 nha!

x:3/7=13/15-2/5

x:3/7=7/15

      x=7/15x3/7

      x=1/5

chúc bạn học tốt

\(x\times\frac{4}{7}+\frac{1}{3}\times x=\frac{2}{3}\)

\(x\times\left(\frac{4}{7}+\frac{1}{3}\right)=\frac{2}{3}\)

\(x\times\frac{19}{21}=\frac{2}{3}\)

\(x=\frac{2}{3}:\frac{19}{21}\)

\(x=\frac{2}{3}\times\frac{21}{19}=\frac{14}{19}\)

cảm ơn bé sói nha

999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999

câu hỏi đâu bạn