Question

x + y = - 6
x - Y = - 10​

Answer 1

$\left \{ {{x + y = - 6} \atop {x - y = - 10}} \right. \\2x = - 16\\x = \frac{- 16}{2} \\x = - 8$

Verificando:

x + y = - 6

- 8 + y = - 6

y = -  6 + 8

y = 2

x - y = - 10

- 8 - y = - 10

- y = - 10 + 8

- y = - 2 .(-1)

y = 2

S = (- 8, 2)