SOLUTION: Let f(x) = x^2 + 4x - 31. For what value of a is there exactly one real value of x such that f(x) = a?

Question 1096609: Let f(x) = x^2 + 4x - 31. For what value of a is there exactly one real value of x such that f(x) = a?
Answer by ikleyn(52780) (Show Source): You can put this solution on YOUR website!
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HINT: this value of x and this value of "a" form the vertex of the given parabola.

     =  = .


    So, this value of "a" is  a = -35,  and this value of "x" is  x = -2.

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