Answer:
200
Explanation:
Given that C(x) = 0.1 - 40x +9569,
complete the square, then C(x) = 0.1* ( - 400x) +9569
= 0.1 * ( - 400x + ) +9569 -
= 0.1 * (x - 200)^2 - 30431
so the answer is 200 machines
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