Question

ПОМОГИТЕ СРОЧНО АЛГЕБРААА 8 КЛАССС
Система линейных уравнений

Answer 1

$\left \{ {{2x-y=5} \atop {x-5,5y=15}} \right.$$\left \{ {{2x-y=5} \atop {-2x+11y=-30}} \right.$$;10y=-25;$$y=-2,5;$$2x-(-2,5)=5;$$2x=2,5$$x=1,25$

Answer 2

$\left \{ {{2x-y=5} \atop {x-5,5y=15}} \right.\\\\\left \{ {{x=15+5,5y} \atop {2*(15+5,5y)-y=5}} \right. \\\\\left \{ {{x=15+5,5y} \atop {30+11y-y=5}} \right.\\\\\left \{ {{x=15+5,5y} \atop {10y=-25}} \right.\\\\\left \{ {{x=15+5,5y} \atop {y=-2,5}} \right.\\\\\left \{ {{x=15+5,5*(-2,5)} \atop {y=-2,5}} \right.\\\\\left \{ {{x=15-13,75} \atop {y=-2,5}} \right.\\\\\left \{ {{x=1,25} \atop {y=-2,5}} \right.$