Answer:
2
Step-by-step explanation:
For elimination problems, you have to have the variables that you want to cancel out equal in value but opposite in sign.
Since you are trying to cancel out y and you are changing the second equation, look at the first equation.
The y variable is +2y. This means that the second equation with a y variable of -2y.
Since the the second equation's y variable is -y, multiply it by 2.
-y x 2 = -2y
