Ответ:

x+y=-5; [*4]

4x-y=-5;

4x+4y=-20;

4x-y=-5;

Вычитаем:

4y+y=-20(-(-5));

5y=-20+5;

5y=-15;

y=-3;

x+(-3)=-5;

x=-5+3;

x=-2;

[tex]\displaystyle\bf\\+\left \{ {{x+y=-5} \atop {4x-y=-5}} \right. \\--------\\5x=-10\\\\x=-10:5\\\\x=-2\\\\y=4x+5=4\cdot(-2)+5=-8+5=-3\\\\\\Otvet \ . \ (-2 \ ; \ -3)[/tex]