Предмет: Математика, автор: lanaem

решите уравнения с помощью подставки {5x-2y=15 2x-y=7
помогите сейчас прошу,нужно сдать сор,поставлю много баллов

Ответы

Автор ответа: Аноним
1

Ответ:  х=1 ; у=-5.

Пошаговое объяснение:

{5х-2у=15

{2х-у=7

у=2х-7  (из второго уравнения).

Подставляем в первое уравнение.

5х-2(2х-7)=15

5х-4х+14=15

х=15-14=1.

у=2*1-7=-5.

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