Answer:
(C) Multiply the bottom equation by 2.
Step-by-step explanation:
The given equation are:
(1)
and
(2)
Now, in order to add these equations and eliminate y, we should multiply the bottom equation by 2, thus we have
(3)
(4)
Now, adding the above equations, we have


Now, substituting the value of x in equation (3), we have


Therefore, option (C) is correct.