What change is needed to make this relation a function?
{(1, 2), (2, 5), (3, 8), (3, 9)}

Change the 8 to a 5.

Change one of the 3's to a number not yet used.

Change both 2's to 6's.

No changes are needed.

Question

What change is needed to make this relation a function?
{(1, 2), (2, 5), (3, 8), (3, 9)}

Change the 8 to a 5.

Change one of the 3's to a number not yet used.

Change both 2's to 6's.

No changes are needed.

phi · Answer

A function does not have the same x with different y's
if you have a pair (x0,  y0) and (x0, y1), then it is not a function because x0 is paired with 2 different y's

so if you see an (x,y) pair that has the same x value as another (x,y) pair, you have to get rid of one of the pairs,  or change the x value of one of the pairs.