Final answer:
The choice of variable names doesn't affect the correctness of the answer.
Step-by-step explanation:
When solving a problem with two variables, the choice of variable names doesn't affect the correctness of the answer. In this case, one student used x for the first variable and y for the second variable, while the other student used x for the second variable and y for the first variable. The only difference is the way the variables are labeled; the answers themselves are the same.