Question 1044898
The minimum point for f occurs in the x value the exact MIDDLE of x=-4 and x=4, meaning at x=0.  What is the corresponding y-coordinate?  


f has vertex as a minimum, opens upward, and so all y-values are greater than or equal to {{{f(0)}}} or {{{y>=(0^2-16)/7}}}.


{{{graph(300,300,-6,6,-6,6,(1/7)(x^2-16))}}}



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correction to range inequality was made, so graph should be reliable now.



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I had discussed RANGE, but original question was about DOMAIN.  What is the set of possible acceptable values for x?  ALL REAL NUMBERS is this set.  All real numbers {{{-infinity<x<infinity}}}.