Question

{2x-2y=12
{x+2y=11 ?????

Answer 1

2x - 2y = 12
2x = 12 + 2y
x = 6 + y (I)

x + 2y = 11
(6 + y) + 2y = 11
6 + 3y = 11
3y = 5
y = 5/3

Substituindo em (I)
x = 6 + 5/3
x = 18/3 + 5/3
x = 23/3