Mathematics - 12 December 2007

The one with the correct answer gets the best answer!! U have to have all the decimals also... Good luck!

2007-12-12 09:17:31 · 11 answers · asked by C5701 2

3x+5y=2
x+4y= -4

I've solved all my other problems, but this one is giving me trouble. I must find x and y (the problems are the same; x and y equal the same in both problem.

Please help?

2007-12-12 09:11:52 · 7 answers · asked by Anonymous

an isosceles triangle has two sides of length a, and the angle between them is θ. Write the area A of the triangle in terms of a and θ. Then find the area of the triangle when a = 10 inches and θ = 30°.

please show as much work as possible


thanks for your help

2007-12-12 09:04:52 · 2 answers · asked by lynnsteichen 2

I am having trouble with this math problem in calculus:
The CDC has discovered a new highly contagious disease. They estimate that t days after the disease is first observed in a community, the percent of the population infected by the disease is approximated by P(t) = 20t^3 - t^4 / 1000 for 0 less than or equal to t less than or equal to 20. When will the population reach maximum infection? What percent of the population will be infected?

2007-12-12 09:03:22 · 2 answers · asked by qtpooh83 2

1. Given the ratios of the lengths of the sides of triangle DEF and triangle XYZ. Is triangle DEF similar to triangle XYZ?
Triangle DEF 1:1:2
Triangle XYZ 3:3:6

A)Yes
B)No
C)Cannot be determined


2. Solve the following proportion
3/y + 2 = 2/y

A)4
B)1
C)3
D)2

2007-12-12 08:56:20 · 3 answers · asked by Anonymous

3 (4/9) (-4) (6/4)

5 (3/4) (-4) (-2)


I really want to know how to do these problems I just don't want the answers I want an explaintion of the overall material as well

2007-12-12 08:52:55 · 3 answers · asked by TheMiddleisSafe 3

4 hikers have to cross a bridge. The bridge wiill collapse in exactly 17 minutes. It is pitch black outside and they only have 1 flashlight between them. The hikers all cross at different rates; one can cross in 1 minute another crosses in 2 minutes, and the others cross in 5 and 10 minutes respectively. The group of 2 travels at the slower hikers rate. The hikers can only cross in groups of 2 at the most. Each group has to have the flashlight give to them by hand. No tricks allowed, such as 1 hiker carries another, they throw the flashlight, or they go halfway and shine the light, ect. Thanx for the help!

2007-12-12 08:47:51 · 4 answers · asked by Jenna F 2

2007-12-12 08:45:21 · 2 answers · asked by Alex P 1

How many steps in one meter?

2007-12-12 08:44:28 · 5 answers · asked by Hmm 1

Let A, B, and C be r.v.'s. Below is their joint density function:

f_A,B,C of (a, b, c) =
2/3(a+b+c) when 0 ≤ a,b,c ≤ 1 and
0 elsewhere

find the probability that A ≤ 1/2.

2007-12-12 08:40:41 · 1 answers · asked by cornzxo 1

can someone help me with these math problems??

x^2 + x + 5 = 0

x^2 + 4x +1 = 0

Please help me start them off!! thanks

2007-12-12 08:40:34 · 5 answers · asked by Fuzzyglasses 3

i have to expand and simplify these...
x(x+1)+1(x+1)

s(s+4)-2(s+4)

please help
much thanks

2007-12-12 08:40:12 · 7 answers · asked by Anonymous

How do I simplify this:

i^3(4-3i)

Show in steps and explain. Thanks!

2007-12-12 08:39:16 · 2 answers · asked by cgarletts 1

x,y and z represent lengths
a) x+y
b) xy
c) xy/z
d) x/y+z
Could some please explain this to me? I'm not sure on this dimensional analysis, I got: length, area, volume and area
Thanks

2007-12-12 08:26:01 · 8 answers · asked by Anonymous

could you please show how you did it, i have a whole bunch more i have to do and i dont know how to do them.

17. A container is partially filled with 12 liters of whole milk containing 4% butterfat. How much 1% milk must be added to get a mixture that is 2% butterfat?

18. An 80-pound grass seed mixture is 30% bluegrass seed. How many pounds of seed containing no bluegrass seed (0%) should be added to the seed mixture for a resulting blend that is 20% bluegrass seed?

2007-12-12 08:20:32 · 2 answers · asked by Anonymous

Prove that the function defined by f(x) = (x-1/2) / [ x * (x-1) ] defines a bijection between (0,1) and R.

(R defining the set of real numbers)

2007-12-12 08:13:41 · 2 answers · asked by Anonymous

2007-12-12 08:10:28 · 6 answers · asked by mel 3

I need to find the numbers and I am having trouble finding them! Can some one please help?

2007-12-12 08:09:51 · 2 answers · asked by Amanda S 2

can someone please help factor this:

n²-6n = 0

2007-12-12 08:08:08 · 3 answers · asked by Alaina 1

In this problem calculate the integral from 0 to 2 of f(x) =((x^2)/3 + 2 )dx by using the definition int of a to b of f(x) dx = lim of n to infty Sn {i=1}^{n} f(x_i)*Delta x
The summation inside the brackets is R_n which is the Riemann sum where the sample points are chosen to be the right-hand endpoints of each sub-interval.

Calculate R_n for f(x) = (x^2)/3 + 2 on the interval [0, 2] and write your answer as a function of n without any summation signs

R_n = ?
lim_{n to infty} R_n = ?

2007-12-12 08:02:30 · 1 answers · asked by Anonymous

desperate help needed

2007-12-12 07:46:08 · 19 answers · asked by Anonymous

i have this mathematician project that counts as my semester exam and i cant find what my guy invented or how he contributed to math

2007-12-12 07:42:35 · 13 answers · asked by daddys princess 1

2007-12-12 07:41:14 · 4 answers · asked by Cookie A 1

Simplify as much as possible making all exponents positive. Assume all variables represent positive numbers.
125^1/3

12^-3/2

x^3/5 * x^1/2

(9x^4y^2) ^1/2

(27x^3) ^-1/3
*I missed this day of class, can anyone help??

2007-12-12 07:38:39 · 4 answers · asked by mel 3

Gravel is being dumped from a conveyor belt at a rate of 40 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always the same. How fast is the height of the pile increasing when the pile is 24 feet high? Recall that the volume of a right circular cone with height h and radius of the base r is given by V = [1/3]πr2h.

2007-12-12 07:37:57 · 2 answers · asked by Joe B 2

A particle moves along a straight line with equation of motion s = t5 − 5 t4 Find the value of t (other than 0 ) at which the acceleration is equal to zero.

2007-12-12 07:37:11 · 2 answers · asked by Joe B 2

3√6 - 6 √150

a. 27√6
b. 2√6
c. -3√6
d. -27√6

2007-12-12 07:33:43 · 6 answers · asked by . 1

Please help.

2007-12-12 07:31:31 · 4 answers · asked by Aira A 1

√49z^28 / 9

a. 49z^14 / 9
b. 7z^14 / 9
c. 7z^14 / 3
d. 7z^26 / 3

2007-12-12 07:28:31 · 7 answers · asked by . 1

2007-12-12 07:00:52 · 2 answers · asked by tazzerz 1