Respuesta :

Samuraizk

Answer:

I think its:

Q1= x=(9+y)/2

Q2= x=(-20-6xy)/4

Step-by-step explanation:

Q1)

X-y=9

2x-y=9

2x=9+y

x=(9+y)/2

Q2)

4x-2y=-20

4x-2(-3x)=-20

4x+6xy=-20

4x=-20-6xy

x=(-20-6xy)/4