Question

resolva o sistema:
x + y =4
x - y =8 ​

Answer 1

Resposta:

x = 6

y = -2

Explicação passo-a-passo:

$\left \{ {{x + y =4} \atop {x - y = 8}} \right. \\\\ x = 4 - y\\\\4 - y - y = 8\\- 2y = 8 - 4\\-2y = 4\\y = -2\\\\x = 4 - y\\x = 4 - (-2)\\x = 4 + 2 \\x = 6$