Mathematics - 18 December 2007

Let's say I want to divide a rope 100 meters long into 25 parts. Each part must have a unique length but the sum of all parts must still be 100 meters.
2 cases are of interest to me:
case 1: i dont care to know or set the size of any parts as long as they sum up to 100 meters and the rate of change should not change from one part to the next (linear?).
case 2: I want to be able to set the size of the biggest part AND the size of the smallest part, both these 2 parts together should not be more than 50 meters or half the total of 100 meters and all the 25 parts together should of course still sum up to 100 meters. In this case the solution should not be linear.
It seems to me reminiscent of some financial formula like npv but I can't figure it out. Help!

2007-12-18 16:10:45 · 1 answers · asked by publicvoidpjr 1

Directions: Write the factored form of each expression.

1. -xy + 21 + 7x -15

2. -3(x)squared - (y)squared z + (x)squared z + 3(y)squared


yeahh I suck at math haha but please help.

thank you

2007-12-18 16:09:58 · 1 answers · asked by Anonymous

y=-5x^2-8x+2

2007-12-18 16:05:53 · 2 answers · asked by shatterpulse 1

First, your sequence is: 1, 1, 5, 13, 25, 41, 61

Take the differences between adjacent terms:0, 4, 8, 12, 16, 20

Take the difference again: 4, 4, ,4 ,4, 4

Notice that all the second differences are the same. This means the polynomial will be second order so the sequence must look like:

a*n^2 + b*n + c

Now its a matter of solving for a, b, and c. If you call this last difference (here its 4) k and your highest exponent m (here that is 2) then a = k/m!

To get the next coefficient (b) subtract a*n^2 from each term so the terms become:

1 - 2*1^2 = -1
1 - 2*2^2 = -7

You don't need to do the whole sequence, you only need to do one term more than the exponent you are trying to solve for. you get -6, -6, -6, -6, etc.
Using the formula for coefficients above b = -6/1! = -6

So the sequence formula so far is 2*n^2 - 6*n + c

To find c, just evaluate for n=1: 2*1^2 - 6*1 + c = 1
So: c=5
---------------------------------
why is difference -6 not 6? why is formula for c equal to 1?

2007-12-18 15:55:46 · 4 answers · asked by Anonymous

Find the measure of each angle in the polygon.
Thanks :]

http://i11.tinypic.com/8ebl0cg.jpg

2007-12-18 15:55:09 · 6 answers · asked by Anonymous

I have been assured that the roots x=-1 and x=-2 are both extraneous.. and I reason has been explained to me, but I can't wrap my brains around it. When I check the roots by substituting them back into the original equation
sqrt(1) = -1 and sqrt(4) = -2
they appear to be true statements. HELP!

2007-12-18 15:41:57 · 3 answers · asked by Anonymous

In triangle ABC, AB = 14, BC = 15, and AC = 13. A square is inscribed in triangle ABC with one side on AB. What is the length of the side of the square?

2007-12-18 15:38:46 · 5 answers · asked by yu.s@att.net 2

1. 27^x / 9^(2x-1) = 3^(x+4) answer= -1

2. 8^1/4 * (1/4)^x/2 = 16^3/4 answer is-9/4

i tried both of these and well I am unsure where to begin as i tried getting the bases the same and reducing as well following all the exponent rules but can't geet these answers Please Help me!

2007-12-18 15:36:11 · 4 answers · asked by Anonymous

20,15,10

2007-12-18 15:31:41 · 8 answers · asked by Anonymous

A farmer wants to build a rectangular fence. 3 sides will be made out of cement and cost $10/feet. 1 side will be made out of bricks and will cost $30/ feet. The area is to be 20 ft^2. Minimize the cost.

2007-12-18 15:25:40 · 3 answers · asked by Quest 1

2007-12-18 15:23:26 · 14 answers · asked by Anonymous

Ok, I've been doing this homework for hours and still don't fully understand it. I have this problem, 4m-n=6 and I have to solve for n. I got it down to -n= 6/4m. what do I do with the -n?? Divide both sides by one perhaps? Plz help.

2007-12-18 15:23:26 · 6 answers · asked by Anonymous

Please explain youurself and give an example!!!! Thnks!

2007-12-18 15:09:46 · 8 answers · asked by Anonymous

2007-12-18 15:08:18 · 3 answers · asked by SHI 1

what if a problem had 3 different letters. how would you construct the truth table?

lets use a,b, and c

a would be true, true, false false
then b would be true, false , true , false

but what would c be?

2007-12-18 15:07:40 · 4 answers · asked by xrandomnessx 2

2007-12-18 15:07:36 · 3 answers · asked by Anonymous

2007-12-18 15:04:10 · 1 answers · asked by wej1rebmun 1

give examples.

2007-12-18 14:58:44 · 7 answers · asked by nerris121 4

6x-3y=42
4x+2y=-4

what is x+y?

2007-12-18 14:57:04 · 6 answers · asked by Lisandra 1

The bill for 3 glasses of orange juice and 5 pancake specials is $7.60, but the bill for 5 glasses of orange juice and 4 pancake specials is $7.90. What is the cost of 1 glass of orange juice? What is the cost of one pancake special?

2007-12-18 14:56:07 · 9 answers · asked by Amanda S 2

78! + 79! = 9.0594E+116 if this helps....

2007-12-18 14:55:14 · 7 answers · asked by PhillyT 1

Linear and Quadratic Modeling Application Report

Selecting and Interpreting Your Model: In Weeks 3 and 4, you used the linear and quadratic models you created to forecast the food CPI for the next month. Include both forecasts in your report. Then, plot your forecast on the same graph as the data for each of the models. Use a visual inspection to decide which appears to best fit the general pattern of the data. Explain why you chose your model.

Writing the Report: Once you have decided on a model, write your report using the following format

2007-12-18 14:41:13 · 1 answers · asked by Nicole 4

Find where the slope is defined:

x^3 + y^3 = xy

Wouldn't it just be the following:

3x^2 + 3y^2*(dy/dx) = x*(dy/dx)+y

3y^2*(dy/dx) -x*(dy/dx) = -3x^2+y
(dy/dx)(3y^2-x) = -3x^2

so: (dy/dx) = (-3x^2 + y)/(3y^2 -x) ??

Thanks a lot, 10 pts to first correct answer

2007-12-18 14:28:58 · 3 answers · asked by Work Hard, Make Money, Enjoy Life... 3

the lenght of a rectangle is 4ab. the width is 2ab. find the perimeter of the rectangle in terms of ab. please show work or at least enough to show me how to do it.

2007-12-18 14:25:28 · 5 answers · asked by Anonymous

2007-12-18 14:21:53 · 1 answers · asked by purvish1997 2

This problem on my assignment is giving me trouble

2007-12-18 14:17:13 · 6 answers · asked by Anonymous

http://i59.photobucket.com/albums/g319/villiansk8er5148/5457.jpg

2007-12-18 13:49:45 · 7 answers · asked by Anonymous

A locker combination system uses three digits from 0 to 9. How many different three-digit combinations with no digit repeated are possible? The Answers are 30, 504, 720, 1000. Which one is it? I said 504.

2007-12-18 13:47:25 · 6 answers · asked by Josh Kaz 3

which multiple choice answer is right


http://i59.photobucket.com/albums/g319/villiansk8er5148/4567.jpg

2007-12-18 13:45:47 · 3 answers · asked by Anonymous

2007-12-18 13:43:11 · 2 answers · asked by justin k 1