Question 1000824:  Which of the following relations is a function?
 
    (8, 1), (-4, 4), (4, 1), (8, 2)
 
    (4, 4), (-4, 6), (4, 3), (-7, 2)
 
    (4, 4), (-4, 2), (8, 1), (-7, 2)
 
    (4, 0), (-4, 3), (8, 1), (-4, 5) 
 Answer by MathLover1(20850)      (Show Source): 
You can  put this solution on YOUR website!  
 Function:  A function is a set of ordered pairs in which each  -element has only    -element associated with it.
 
(8, 1), (-4, 4), (4, 1), (8, 2)=>
 
the x-element   is paired with a y-element of   and also a y-element of  
 
so,the relation shown above is NOT a function 
 
 
 
    (4, 4), (-4, 6), (4, 3), (-7, 2)
 
the x-element   is paired with a y-element of   and also a y-element of   
so,the relation shown above is NOT a function 
 
 
 
 
    (4, 4), (-4, 2), (8, 1), (-7, 2)
 
none of the x-element  is paired with a more than one y-element;so,the relation shown above IS a function 
 
 
 
    (4, 0), (-4, 3), (8, 1), (-4, 5)
 
the x-element   is paired with a y-element of   and also a y-element of   
so,the relation shown above is NOT a function 
 
 
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