Question

X+y=1 4×+7y=10 S=(1,2)

Answer 1

{x+y = 1

4x + 7y = 10

}

y = 1 - x

4x + 7(1 - x) = 10

4x + 7 - 7x = 10

-3x = 10 - 7

-3x = 3 (.-1)

3x = 3

x = 3/3

x = 1

---------

y = x -1

y = 3 - 1

y = 2

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Resposta: S = {1,2}