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Your solutions are correct. I mean, you have the set of four solutions correctly.
Their ordering instruction is presented in a very strange way.
You can order the pairs looking in x first, but then you have no choice to order in y.
It forces me to think that they ask you to make your ordering TWICE:
- first time by ordering 4 pairs looking in x;
- and the second time by ordering the same 4 pairs looking in y.
In any way, it is not a Mathematical way to formulate an assignment.
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The two other tutors presented the solutions to the roots, although nobody asked them to do it - you just have the solutions correctly.
The post by @josgarithmetic is the way to NOWHERE, as it often happens with him - so you can simply IGNORE his post, for your safety.