Question 597551
Are you allowed to use a graphing calculator?  If so, type the equation into the calculator, and (by trial and error!!) use a window of x from -10 to 100 and y from -10000 to 100000.


{{{graph(300,300,-10,100,-10000,100000, -75x^2+5925x-47250)}}}


The break-even points will be the values of x where the profit P(x) = 0.  This occurs at x=9 and x=70.  You can do this by inspection of the graph, or using the graphing calculator techniques.  For the TI84, use 2nd, F4(CALC).  I have a 24 page explanation of the TI84 that is available FREE on my website.  To find my website, use the easy-to-remember and easy-to-spell link www.mathinlivingcolor.com.  Click on the link at the bottom of the page, which takes you to my Homepage.  Near the bottom of my Homepage is a link "Calculator Links and Handouts" that will take you to the pages that you can print yourself.  Believe it or not, I'm not selling anything--it's all FREE!!!


Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus