# Problem solving with quadratic functions.

1. Sep 14, 2011

### davie08

1. The problem statement, all variables and given/known data
Eastern Ceramics can sell up to 200 of its flower pots per day in accordance with the demand function.

p=13 -.04q

write revenue as a function of the quantity sold q. find the output level q that maximizes R and the selling price at this output level.

2. Relevant equations

3. The attempt at a solution

okay i tried to put my attempt on here but it was so far from the answer that it would likely confuse you lol.

2. Sep 14, 2011

### HallsofIvy

Staff Emeritus
Then why post it here? At least, what did you use for the revenue function?

3. Sep 14, 2011

### davie08

okay would you use R=a(q-h)^2 + k

4. Sep 14, 2011

Why would you think that? If I give you two numbers, one for quantity sold and the other for selling price ($per unit), how would you compute the revenue? RGV 5. Sep 14, 2011 ### davie08 I really have no clue what to use to figure this out can someone just explain what I have to use and then I will understand it and practice it until I'm ready to use it on a test. 6. Sep 14, 2011 ### HallsofIvy Staff Emeritus What? Where did h, a, and q come from? Thats a general form for a quadratic but you need to use the information from this problem. If you sell 10 items for$5 each, how much money will you receive?

If you sell 50 items for \$3 each, how much money will you receive?

How did you calculate that?

Okay, if you sell q items for p each, how much money will you receive?

7. Sep 14, 2011

### Staff: Mentor

We do not do your schoolwork for you here on the PF. You are getting some very good hints, if you would just put forth some effort to try to understand and use the hints.

8. Sep 14, 2011

### symbolipoint

Posted from davie08:
He is asking about a form appearing to completing the square as a way to solve, hoping the forum members recognize the standard form.

davie08, completing the square is one possible way to find the maximum, but first give us the complete description of the exercise, word-for-word. What is "p" supposed to be? What is "R" supposed to mean?