diket : 2x -y = 2 dan x + 3y = 15 maka nilai 3x -y =...

2x - y = 2      x1   2x - y = 2
x + 3y = 15   x2   2x + 6y = 30
                                  -7y = 28
                                     y = -4
2x - y = 2
2x - (-4) = 2
2x + 4 = 2
2x = 2 +4
2x = 6
x = 3

3x - y = 3(3) - (-4)
= 6 + 4
= 10