What is a subset in math?? for Algebra?

Question

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Answer 1

Kind of hard to explain, but say you have the following numbers,

1, 3, 5, 6, 8, 9, 11.

And for example, a subset of those numbers would be

{3, 6, 9, 11}

All apologies, I'm awful at explaining mathematics over the internet.

Hope I helped.