Answer:
The winning ticket is: A.
.
Step-by-step explanation:
We have been given that Tomas’s math class held a raffle. The student who picked the ticket with a pair of equivalent equations on it would win.
Let us check our given pairs of equations one by one.
A. 
Let us combine like terms on the both sides of our equation.


We can see that both sides of our equation are equal, therefore, option A is the correct choice.
B. 
Let us combine like terms on the both sides of our equation.
Since the both sides of our equation are not equal, therefore, option B is not a correct choice.
C. 
Upon combining like terms we will get,



Since the both sides of our equation are not equal, therefore, option C is not a correct choice.
D. 
Upon combining like terms we will get,



Since the both sides of our equation are not equal, therefore, option D is not a correct choice.