SOLUTION: I am not sure how to set up this problem: The average monthly high temperature (in degrees Fahrenheit) in Cincinnati for the first 10 months of the year can be modeled by the equa

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Question 339885: I am not sure how to set up this problem: The average monthly high temperature (in degrees Fahrenheit) in Cincinnati for the first 10 months of the year can be modeled by the equation y+=+0.21x%5E2+%2B+2.24x%5E2+%2B+2.33x+%2B+33.67+ where x = 1 corresponding to January. What month is the high temperature most likely to be close to 75 degrees?
Thank you so much (I am encouraged to use a TI84 graphing calculator, but that is new to me so I am having trouble with that as well.)
Beth
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


The "right" way to do this is to set your function equal to 75 and solve for . Your function is a bit odd in that you have two terms, which lead me to suspect that you have a small typo and that you really meant:



And using the equation solver at QuickMath.com, you get April if you use your rendering, and March if you use mine. Can't say which is more correct since I don't really know the climate in Cincinnati.

But then I got to digging a little deeper and found that there is something very, very wrong with your model. Even using your rendering of the exponents, the average high temperature in September (month 9) would be 253 degrees.

Get your model right and let me know, we'll talk about where you need to go from here.

John

My calculator said it, I believe it, that settles it