Question

Resolva o sistema x+2y=8, 2x+y=7.

Answer 1

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x + 2y = 8

2x + y = 7

x = 8 - 2y

2(8 - 2y) + y = 7

16 - 4y + y = 7

16 - 3y = 7

3y = 16 - 7

3y = 9

y = 9/3

y = 3

_

x = 8 - 2y

x = 8 - 2(3)

x = 8 - 6

x = 2

__

x = 2

y = 3

S = { 2 ; 3 }

Alternativa A

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