Use the substitution method to find the solution \( [x;y] \) of the following system of equations.
\[ \begin{aligned}
\frac{x+y}x+\frac1{x+y}=1 \\
\frac{2\cdot(x+y)}x-\frac1{x+y}=-7
\end{aligned} \]
Use the substitution method to find the solution \( [x;y] \) of the following system of equations.
\[ \begin{aligned}
\frac{2x}{x+3}-3\cdot\frac{y+2}y=2 \\
\frac x{x+3}+2\cdot\frac{y+2}y=8
\end{aligned} \]
Use the substitution method to find the solution \( [x;y] \) of the following system of equations.
\[ \begin{aligned}
\frac2{x+4}-\frac1{2-y}=-6 \\
\frac1{x+4}+\frac5{2-y}=8
\end{aligned} \]