4x - y=11 dan 2x +3y=9 tentukan nilai 2x - 2y

4x - y = 11 dikali 1
2x + 3y = 9 dikali 2

4x - y = 11
4x + 6y = 18
------------------ -
-7y = -7
y = 1

4x - y = 11
4x - 1 = 11
4x = 11 + 1
4x = 12
x = 12/4
x = 3

maka 2x - 2y = 2(3) - 2(1) = 6 - 2 = 4

maaf kalau salah, semoga membantu