Предмет: Алгебра, автор: prostota00

Помогите помогите пожалуйста решить систему методом подстановки
2x+5y=15,
x+2y=3

Ответы

Автор ответа: KarinaYouchi
0
{2x+5y=15
{x+2y=3   x=3-2y

2(3-2y)+5y=15
6-4y+5y=15
y=9
x+2*9=3
x=3-18
x=-15
Ответ:(-15;9)
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