Question

решиье систему уравнений х+2у=2 3х-у=-1

Answer 1

$left { {{x+2y=2} atop {3x-y=-1}|*2} right\\+left { {{x+2y=2} atop {6x-2y=-2}} right.$

________

7x = 0

x = 0

x + 2y = 2

0 + 2y = 2

2y = 2

y = 1

Ответ : ( 0 ; 1)

Answer 2

x+2y=2

3x-y=-1

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x=2-2y

3(2-2y)-y=-1

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x=2-2y

6-6y-y=-1

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x=2-2y

-7y=-7

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x=2-2y

y=1

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x=2-2

y=1

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x=0, y=1

/x,y/=(0,1/