{12+3y-9=2x+10 8+20=10+2(3x+2y)

Question

{12+3y-9=2x+10 8+20=10+2(3x+2y)

Answer 1

Система

12+3у-9=2х+10

8+20=10+6х+4у

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-2х+3у=10-3  I*3

6х+4у=28-10

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-6х+9у=21

6х+4у=18   сложим

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13у=39;  у=3

2х-3у=-7; 2х=3*3-7;  2х=2; х=1

Ответ: (1; 3)