Question

how can you say if the set of ordered pairs represent a function or not

Answer 1

in a function of x, a single x value can not give more than 1 f(x) [ = y often] value. Or it isn't a function.

when you plug in a number in a function, you expect it to output one number, not a choice of numbers to chose from.

many x values can share the same y though

Answer 2

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