3x+5y=7 dan x-3y=1 hitunglah menggunakan cara subtitusi/eliminasi/campuran mohon bantuannya^^

3x + 5y = 7 | x 1 | 3x +5y = 7
x - 3y = 1 |x 3 | 3x -6y =3
--------------- _
-1y =4
y =4/-1
y= -4
x -3y =1
x -3 . -4 = 1
x + 12 = 1
x = -12+1
x = -11