Question

5x+7y = 22 / 10x+y = 96

Answer 1

$\left \{ {{5x+7y=22} \atop {10x+y=96}} \right.$

Isolando Y:
10x + y = 96
y = 96 - 10x

Substituindo Y:
5x + 7y = 22
5x + 7(96 - 10x) = 22
5x + 672 - 70x = 22
5x - 70x = 22 - 672
- 65x = - 650  (* -1)
65x = 650
x = 650 / 65
x = 10

Substituindo X:
10x + y = 96
(10 * 10) + y = 96
100 + y = 96
y = 96 - 100
y = -4

Resposta: X = 10 e Y = -4 ----> S={(10, -4)}