Предмет: Математика, автор: lizokd02

[3(5-4x)-2(5y-7)=23,
4(3y-2)-(2+3x) = 32.

Ответы

Автор ответа: iramazurk
4

Ответ:

(-2; 3)

Пошаговое объяснение:

{3(5 - 4х) - 2(5у - 7) = 23

{4(3у - 2) - (2 + 3х) = 32

{15 - 12х - 10у + 14 = 23

{12у - 8 - 2 - 3х = 32

{-12х - 10у = 23 - 15 - 14

{-3х + 12у = 32 + 8 + 2

{-12х - 10у = -6

{-3х + 12у = 42 | * -4

{-12х - 10у = -6

{12х - 48у = -168

{-58у = -174

{12х - 48у = -168

1)

-58у = -174

у = -174 : (-58)

у = 3

2)

12х - 48у = -168

12х - 48 * 3 = -168

12х - 144 = -168

12х = -168 + 144

12х = -24

х = -24 : 12

х = -2

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