Question

b)
(x - y = 1
(x + y = 9​

Answer 1

Resposta:

x - y = 1

x = 1 + y

x + y = 9

1 + y + y = 9

2y = 9 - 1

2y = 8

y = 8/2

y = 4

x = 1 + y

x = 1 + 4

x = 5

Par ordenados: {x = 5, y = 4}