Respuesta :

1,-4 sorry if wrong :(

Step-by-step explanation:

1.3x+2y=13

3x+2y+-2y=13+-2y

3x=-2y +13

3x/3=2y+13/3

The answer is x= -2/3 y+13/3

2.x= -2/3 y+ -1/3 z +13/3

3.x= -1/5 y +9/5