Question

me ajudem pfvr
determine o conjunto solução do sistema: {5x+3y=7
5x-3y=13

Answer 1

$\left \{ {{5x+3y=7} \atop {5x-3y=13} \right.$

$\to 5x=13+3y$

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$5x+3y=7$

$(13+3y)+3y=7$

$13+3y+3y=7$

$6y=7-13$

$y=-\frac{6}{6} =-1$

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$5x-3y=13$

$5x-3(-1)=13$

$5x+3=13$

$5x=13-3$

$x=\frac{10}{5} =2$

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x=2 e y=-1