tolong bantuanya untuk no.4

Bab Matriks
Matematika SMA Kelas X

2x - y = -2
x + y = -8
---------------- +
3x = -10
x = -10/3

x + y = -8
-10/3 + y = -8
y = 10/3 - 8
y = 10/3 - 24/3
y = -14/3

2x + y = 2 . (-10/3) + (-14/3)
           = -20/3 - 14/3
           = -34/3
           = - 11 1/3