Question

Здравствуйте, пожалуйста можете помочь с 3 номером срочно даю 20 баллов !!!​

Answer 1

Ответ:

1. x = -5; y = 2
2. x = 3; y = -2
3. x = -1; y = 1

Пошаговое объяснение:

1. $\left \{ {{x = -7 + y} \atop {2x - 3y = -16}} \right.\\2(y - 7) - 3y = -16\\2y - 14 - 3y = -16\\y = 2\\x = -7 + 2 = -5$
2. $\left \{ {{y = x - 5} \atop {4x + y = 10}} \right.\\4x + x - 5 = 10\\5x - 5 = 10\\5x = 15\\x = 3\\y = 3 - 5 = -2$
3. $\left \{ {{-x = 3 - 2y} \atop {x - 5y = -6}} \right.\\\left \{ {{x = 2y - 3} \atop {x - 5y = -6}} \right.\\2y - 3 - 5y = -6\\-3 - 3y = -6\\3y = 3\\y = 1\\x = 2 - 3 = -1$