Question 167387
C(x)=0.01x^2-4x+1500 
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Since the coefficient associated with the x^2 term is "positive" (think happy face), the parabola will open upward like a U.  Knowing this, if we find the vertex, we'll find the minimum.
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The axis of symmetry is the line x = -b/2a
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x = -(-4)/2(0.01)
x = 4/0.02
x = 200 (items produced to minimize cost)
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To find the cost, plug the value above back into:
C(x)=0.01x^2-4x+1500 
C(200)=0.01(200)^2-4(200)+1500 
C(200)=400-800+1500 
C(200)=-400+1500 
C(200)=$1100 (minimum cost)