Решите систему

Решите задачу:

$\left \{ {{5(x+2y)-3=x+5} \atop {y+4(x-3y)=50}} \right. \ \textless \ =\ \textgreater \ \left \{ {{5x+10y-3=x+5} \atop {y+4x-12y=50}} \right. \ \textless \ =\ \textgreater \ \left \{ {{4x+10y=8} \atop {4x-11y=50}} \right. =\ \textgreater \ \\=\ \textgreater \ \left \{ {{x= \frac{8-10y}{4} } \atop {4*\frac{8-10y}{4}-11y=50}} \right. =\ \textgreater \ \\4*\frac{8-10y}{4}-11y=50};\\8-10y-11y=50;\\-21y=42;\\y= \frac{42}{-21} =-2;\\\left \{ {{x= \frac{8-10y}{4} } \atop {y=-2}} \right.\ \textless \ =\ \textgreater \ \left \{ {{x=7} \atop {y=-2}} \right.$