Question

Me ajudem nesse sistema: {x-y=-5
{×"+y''=13

Answer 1

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

2x = 8

x = 8/2

x = 4

x + y = 13

4 + y = 13

y = 13 - 4

y = 9

S = {4, 9}