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| Question 1139591:  The cost C (in dollars) for a company to produce and sell x thousand gadgets is given by
  What is the minimum cost?
 I've found that the start up cost is 2530 dollars.
 Answer by jim_thompson5910(35256)
      (Show Source): 
You can put this solution on YOUR website! I think you meant to say
  instead of  The difference is that the
  term is not in the denominator. To make sure you do not divide by
  , you would write it like this C = (1/30)x^2 - 2x + 2530
 
 
 If my assumption is correct, then we have an equation in the form
 
  where
 a = 1/30
 b = -2
 c = 2530
 
 Use the 'a' and 'b' values to compute the value of h, which is the x coordinate of the vertex
 h = -b/(2a)
 h = -(-2)/(2*(1/30))
 h = 2/(2/30)
 h = (2/1) / (2/30)
 h = (2/1) * (30/2)
 h = (2*30)/(1*2)
 h = 60/2
 h = 30
 The x coordinate of the vertex is 30.
 
 
 The y coordinate of the vertex is k, which is defined as k = f(h)
 For this problem, k = f(30)
 In other words, we plug in x = 30 to find the y coordinate of the vertex.
 
   
 
  Replace every x with 30; use PEMDAS to simplify 
 
   
 
   
 
   
 We see that k = 2500, meaning the y coordinate of the vertex is 2500.
 
 The vertex is at (h,k) = (30, 2500) which in this case is the lowest point of the parabola. The parabola has a lowest point any time
  (in this case, a = 1/30 = 0.033 approximately) 
 The graph confirms the answer
 
  The graph was created with GeoGebra (free graphing software). I used the "min" feature in GeoGebra to find/display point A as shown in the diagram above.
 
 The vertex point (30, 2500) means that if you produce and sell 30 thousand gadgets, then the minimum cost is $2500
 
 side note: keep in mind that x is in thousands. So x = 30 really means 30,000.
 
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 Answer:
 The minimum cost is 2500 dollars
 
 
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