SOLUTION: Let {{{f(x)=x^2+12x+c}}}. For which value of c will f(x) have one distinct root?

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Question 542236: Let f%28x%29=x%5E2%2B12x%2Bc. For which value of c will f(x) have one distinct root?
Answer by mathie123(224) About Me  (Show Source):
You can put this solution on YOUR website!
We know that if the discriminant b%5E2-4ac is equal to zero, then the expression will only have one distinct root.
This means that
12%5E2-4%281%29%28c%29=0
144-4c=0
144=4c
c=36
Therefore c=36 will ensure that f(x) has one distinct root.