Function: Each x maps to one single y, no matter that is the same y. |
Not Function: For x = -4 there are infinitely many y's. |
Not Function: x = 3 maps to four y's. |
Function: Each x maps to one single y, no matter that is is the same y = 2. |
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(4,0),(3,1),(12,5),(4,-6),(-2,4)
Not Function, two sets of points have the same x entry 4, mapping once towards 0 and once to (-6). |
Function: Each entry in the top row is different. |
(0,0),(3,1),(12,5),(4,-6),(-2,4)
Function: There are no two parenthesis with the same x. |
Not Function. On the top row with the input, x = -1 appears twice mapping to two different y values. |