Question

a) x + y =3
3x -y =1






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Answer 1

Resposta:

x = 1 e y = 2

Explicação:

Answer 2

$\left \{ {{x+y=3} \atop {3x-y=1}} \right.$

$\left \{ {{y=3-x} \atop {3x-y=1}} \right.$

$\left \{ {{3x-(3-x)=1} \atop {3x-y=1}} \right.$

$\left \{ {{x=1} \atop {3(1)-y=1}} \right.$

$\left \{ {{x=1} \atop {y=3-1}} \right.$

$\left \{ {{x=1} \atop {y=2}} \right.$