SOLUTION: Given the quadratic function f(x) = x^2 – 6x + 9, find a value of x such that f(x) = 25. This is what I have: x^2 - 6x + 9 = 25 x^2 - 6x - 16 = 0 x^2 - 8x + 2x -16 = 0 x(x-8

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Given the quadratic function f(x) = x^2 – 6x + 9, find a value of x such that f(x) = 25. This is what I have: x^2 - 6x + 9 = 25 x^2 - 6x - 16 = 0 x^2 - 8x + 2x -16 = 0 x(x-8      Log On


   

Question 409452: Given the quadratic function f(x) = x^2 – 6x + 9, find a value of x such that f(x) = 25.
This is what I have:
x^2 - 6x + 9 = 25
x^2 - 6x - 16 = 0
x^2 - 8x + 2x -16 = 0
x(x-8) + 2(x-8) = 0
(x-8)(x+2) = 0
x = 8
Found 2 solutions by ewatrrr, solver91311:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Given the quadratic function f(x) = x^2 – 6x + 9, find a value of x such that f(x) = 25. 

f(x) = x^2 – 6x + 9

x^2 - 6x + 9 = 25

(x-3)^2 -9 + 9 = 25    |completing the square

 (x-3)^2 = 25

  (x-3) = ± 5

   x = 3 ± 5

  x = 8 and x = -2 



CHECKING our Answer(s)***

x^2 - 6x + 9 = 25

 64 - 48 + 9 = 25

 4 + 12 + 9 = 25

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Given the wording of the question, your answer is 100% correct. I say this because the question asks: "...find a value of x...", and that is precisely what you did; the fact that there is another equally valid answer to the question, namely , notwithstanding.


John

My calculator said it, I believe it, that settles it
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