Answer:
x=8
y =4
Step-by-step explanation:
x + y = 12 if x = 2y
Replace x with 2y in the first equation
2y+y = 12
Combine like terms
3y =12
Divide by 3
3y/3 =12/3
y = 4
Now we can find x
x=2y
x=2(4)
x = 8
