Question 1114925
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A student claims that the relation (0,3), (1,5), (3,8), (5,5) is morning a function because the y- coordinate 5 responds 
to more than one x- coordinate. Explain the students error and justify your answer. 
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<U>First</U>, &nbsp;your post was formulated incorrectly.


The correct formulation is &nbsp;<U>THIS</U>:


<pre>
    A student claims that the relation (0,3), (1,5), (3,8), (5,5) is {{{highlight(cross(morning))}}} <U>not</U> a function 
    because the y- coordinate 5 responds to more than one x- coordinate. Explain the students error and justify your answer.
</pre>


<U>Second</U>, &nbsp;the answer by &nbsp;@josgarithmetic is &nbsp;TOTALLY WRONG: &nbsp;&nbsp;this relation &nbsp;<U>actually IS the function</U>,


because each value of &nbsp;"x" &nbsp;(first coordinate) produces a unique response value of &nbsp;"y" &nbsp;("vertical line criterion" is satisfied).



<U>Third</U>, &nbsp;the student's error is in that he (or she - I mean "the student") &nbsp;INCORRECTLY formulates/INTERPRETES &nbsp;the vertical line criterion.


The "vertical line criterion" prohibits to any given "x" of the domain to have more than one response "y".


This criterion is satisfied for the given relation.



The fact noticed by the student that "the y- coordinate 5 responds to more than one x- coordinate" does not relate 
to the "vertical line criterion" and does not disprove it.