Sets, Cartesian product

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Hi guys,
I would like to ask if a set can contain coordinates of points, for example A={[1,3];[4,5];[4,7]} and if we can do Cartesian product of such sets, for example A={[1,3];[4,5]}, B={[7,8];[4,2]} A×B={[1,3][7,8];[1,3][4,2];[4,5][7,8];[4,5][4,2]} (is it correct to write it like that?). I am familiar with doing that when we have sets of numbers (A={1;2}, B={7;5} A×B={[1,7];[1,5];[2,7];[2,5]}). but I am not sure if it is correct with coordinates of points.
Mod note: Fixed typo "carthesian"

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Hi guys,
I would like to ask if a set can contain coordinates of points, for example A={[1,3];[4,5];[4,7]} and if we can do carthesian product of such sets, for example A={[1,3];[4,5]}, B={[7,8];[4,2]} A×B={[1,3][7,8];[1,3][4,2];[4,5][7,8];[4,5][4,2]} (is it correct to write it like that?).
You can write the elements whichever you want, e.g. ##[1,3][7,8]## or ##[1,3;7,8]## or ##[1,3,7,8]## or ##\begin{bmatrix}1&3\\7&8\end{bmatrix}##. It is certainly useful not to mix them like ##[1,7][3,8]##, because this would probably be harder to read, but as long as you're consistent, there is no rule.
I am familiar with doing that when we have sets of numbers (A={1;2}, B={7;5} A×B={[1,7];[1,5];[2,7];[2,5]}). but I am not sure if it is correct with coordinates of points.
I would probably write ##A=\{(1,3),(4,5)\}\; , \;B=\{(7,8),(4,2)\}## as round parenthesis are more common for tuples and commas as separators in a list, and then ##A \times B = \{\; ((1,3),(7,8))\, , \, ((1,3),(4,2))\; , \;((4,5),(4,2))\, , \,((4,5),(4,2))\;\} ## but only in set theory. With different applications, this might change.