Need help with homework word problem

[tlcreyes]

Cost, Revenue, and Profit: the marketing department of a company estimates that the demand for a color scanner is p=100 - 0.0001x, where p is the price per scanner and x is the number of scanners. The cost of producing x scanners is C = 350,000 + 30x and the profit for producing and selling x scanners is P = R - C = xp - C. Use a graphing utility to graph the profit function and estimate the number of scanners that would produce a maximum profit.

 

[pka]

Use a graphing utility to graph the profit function and estimate the number of scanners that would produce a maximum profit.

Well have you done this?

 

[tlcreyes]

yes

when i substitute i get x(100-.0001x)-(350000+30x) and end up with
-.0001x^2+70x-350000

 

[tlcreyes]

plugged that into the calc, but it didn't really make sense to me

 

[stapel]

when i substitute i get....

When you substitute what into where?

Please reply with a clear listing of the steps and reasoning you have attempted. Thank you.

Eliz.