Question

Решите способом подстановки систему линейных уравнений с двумя переменными


{x-y=-10. =>
{2x+y=34

Answer 1

Ответ:

$\displaystyle\left \{ {{x=8} \atop {y=18}} \right.$

Пошаговое объяснение:

$\displaystyle\left \{ {{x-y=-10} \atop {2x+y=34}} \right. \\\\\left \{ {{x=y-10} \atop {2x+y=34}} \right. \\\\\left \{ {{x=y-10} \atop {2(y-10)+y=34}} \right. \\\\\left \{ {{x=y-10} \atop {2y-20+y=34}} \right.\\\\\left \{ {{x=y-10} \atop {3y-20=34}} \right.\\\\\left \{ {{x=y-10} \atop {3y=34+20}} \right.\\\\\left \{ {{x=y-10} \atop {3y=54}} \right.\\\\\left \{ {{x=y-10} \atop {y=\frac{54}3}} \right.\\\\\left \{ {{x=y-10} \atop {y=18}} \right.\\\\\left \{ {{x=18-10} \atop {y=18}} \right.$

$\displaystyle\left \{ {{x=8} \atop {y=18}} \right.$