Решите систему уравнений:

\(\displaystyle\begin{aligned}\begin{cases}\dfrac{5x}{7}=4+\dfrac{y}{5}{\small,}\\\\\dfrac{5x}{7}+y=-20{\small.}\end{cases}\end{aligned}\)

\(\displaystyle x=\) [ ] \(\displaystyle ;\)\(\displaystyle y=\) [ ]\(\displaystyle .\)