## riyor 4 years ago Use the general formula to write the area A of the enclosure as a function of w (that is, only the variable w should appear in the function). it should be a quadratic function

1. 3pwood

What enclosure?

2. myininaya

what is the enclosure? are we enclosing a rectangle or something? or can we enclose whatever we want?

3. riyor

hold on im trying to get the file of the actuall question its part of a project

4. riyor

Its to question number 5

5. riyor

I am completely lost

6. myininaya

maybe this will help

7. 3pwood

Okay, so you have 682 feet of fencing to make up two "width sides" and one "length side" this translates to the equation: 682 = 2W + L You know from basic geometry that the area of a rectangle is length times width: A = L*W What you need to do is solve the first equation for L in terms of W: 682 = 2W + L L = 682 -2W Then substitute that L value into the second function so that you have A in terms of just W: A = L*W A = (682 -2W)W

8. riyor

anyone?

9. myininaya

?

10. myininaya

anyone what?

11. riyor

the site froze on me im taking a look at it now

12. myininaya

ok lol

13. riyor

now if i can get the window correct on my ti 84 :P

14. riyor

any help with that?

15. myininaya

go to Y=

16. myininaya

type 682x-2x^2

17. myininaya

then go to window

18. riyor

yeah i got the equation in its just getting a clear shot of the parabola

19. myininaya

go to where it says x min and type 100 go to where it says x max and type 200 go to where it says y min and type 80 go to where it says y max and type 60000 and see if it looks viewable

20. myininaya

try going to the highest point on the curve and approximate what it is

21. riyor

it works but im going to need both sides of the parabola can i just extend the xmin

22. riyor

holy crap I got it

23. myininaya

no you are fine but you can if you want to

24. riyor

you are amazing!

25. myininaya

did you use the maximum feature on your calculator?

26. riyor

ximn -100 xmax 400 ymin 80 ymax 60000

27. myininaya

no thats not what i meant

28. myininaya

do you see calc?

29. riyor

i havent taken advantage of that yet

30. myininaya

lets do it

31. riyor

i got the max

32. myininaya

do you see maximum

33. riyor

yeah did the whole left and right bound

34. riyor

thats going to give me the best area correct?

35. myininaya

oh nice i got (170.50001,58140.5) this is just an appoximation I arleady found the exact on that pdf file

36. myininaya

your approximation doesn't have to be mine but both of ours should be pretty close to the same thing is yours close to my?

37. riyor

its exact

38. myininaya

k now you remember the file i gave you right? that vertex of the parabola i found by putting the parabola in vertex form gave me the exact (max width,max area)

39. riyor

what file

40. myininaya

scroll up if you haven't seen the file and click on it

41. riyor

looking at it now

42. myininaya

you remember when you uploaded a file i uploaded a file like a few minutes afterwards

43. riyor

yeah i see it

44. riyor

if i have any more questions ill post them

45. myininaya

ok make a new post though because i'm about to leave or do it so you can get someone's attention and bring them back here to help k?

46. myininaya

or 3wood might come back

47. myininaya

gn guys and peace

48. riyor

thanks for all the help both of you are life savers