Shana and Bill are working together to solve the system by substitution. Shana wants to rewrite the first equation to solve for x. Bill wants to rewrite the second to solve for y. Who is correct? Why?
1) Shana is correct, x is easier to use than y is.
2) Bill is correct, y is easier to use than x is.
3) Both are correct, it does not matter which variable you start with.
4) Neither are correct, it is easier to use z than x or y.