Respuesta :

Answer:

1. y = 0

2. x = -5

3. x = 10

4. y = -12

1. 3x+2y=-12, y= -6 3/2
2.-4x+8y=20, x=5+2y
3.x+y=10, x=10-y
4.5x-y=12, y=12+5x