Which set of ordered pairs represents a function?

{(2, –2), (1, 5), (–2, 2), (1, –3), (8, –1)}
{(3, –1), (7, 1), (–6, –1), (9, 1), (2, –1)}
{(6, 8), (5, 2), (–2, –5), (1, –3), (–2, 9)}
{(–3, 1), (6, 3), (–3, 2), (–3, –3), (1, –1)}

A set of ordered pairs is a function as long as no two ordered pairs have the same first coordinate with different second coordinates.

{(2, –2), (1, 5), (–2, 2), (1, –3), (8, –1)}

It is not a function by above definition(since, 1 have 2 images)

{(3, –1), (7, 1), (–6, –1), (9, 1), (2, –1)}

It is a function  

{(6, 8), (5, 2), (–2, –5), (1, –3), (–2, 9)}

It is not a function(since, -2 have more than 1 image)

{(–3, 1), (6, 3), (–3, 2), (–3, –3), (1, –1)}

It is not a function (since, -3 have more than 1 images)

step-by-step explanation:

answers available in this download

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step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.