Question

Which relation is also a function?

{(0, 3), (1, 2), (1, 4), (2, 1))
{(-1,3), (0, 2), (3, -1), (3, 2)}
{(2,-4), (2,-2), (2, 1), (2,3)}
{(-4,-3), (0, -3), (1, -3), (4, -3)}

Answer 1

The correct answer is the final data set: {(-4,-3), (0, -3), (1, -3), (4, -3)}

Explanation:

Functions are determined by the x values, which all have to be different. If the same x value appears twice and has a different y value, it is not a function, but if it appears twice with the same y value also, then it is. You can have the same y value twice, but not the x value unless it has the same y value, making the pair exactly the same. Those are the features of a relation being a function. I hope I said that to where it makes sense. Message me if you need clarification.