Question

Решите систему уравнений способом
сложения
знак системы -x/3+y/5=2,
                        5x/9+y/2=-5;

Answer 1

$left { {{ frac{-x}{3}+ frac{y}{5} =2} atop { frac{5x}{9}+ frac{y}{2} =-5}} right. left { {{-5x+3y=30} atop {10x+9y=-90}} right. left { {{-10x+6y=30} atop {10x+9y=-90}} right. |+ left { {{-5x+3y=30} atop {15y=-60}} right. left { {{-5x-12=30} atop {y=-4}} right.$
$left { {{-5x-12=30} atop {y=-4}} right. left { {{-5x=18} atop {y=-4}} right. left { {{x=-3.6} atop {y=-4}} right.$
Ответ: $(-3.6;-4)$