Question 980179
P(x) = x^2-4000X + 7800000

=> 3,800,000 = x^2-4000X + 7800000

=> x^2-4000X + 40,00,000 = 0

=> x^2- 2*x*2000X + 2000^2 = 0

=> x = 2000 = number of items sold.


Thanks,
PRD
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