Respuesta :

XxAtomicxX

Step-by-step explanation:

x+y=4

x=4-y

4x+8y=20

4(4-y)=20

16-4y=20

-4y=20-16

y=4/-4

y=-1

x+y=4

x+(-1)=4

x=4+1

x=5

hope this helps you

have a nice day