Science & Mathematics - 22 August 2007

2007-08-22 13:48:21 · 7 answers · asked by ExpERT. 3 in Astronomy & Space

If the equation of a circle is x² + y² = r² and the equation of the tangent line is y = mx + b, show that r² (1 + m²) = b².

Hint: After substituting y = mx + b into the circle equation, the resulting quadratic equation has exactly one solution.

2007-08-22 13:48:11 · 4 answers · asked by laffytaffychick13 1 in Mathematics

hey guys! could you please help me about the aromacity of
compounds? and whats the difference between anthracene
and phenanthrene, the 2 simplest compound? please give me
facts about them..

2007-08-22 13:46:15 · 4 answers · asked by Alden ^^ 2 in Chemistry

x-y=0
12x-5y=-21

p+q=4
4p+q=1

m+2n=1
5m+3n=-23

SHOW YOUR WORK!!!!!!!!!!

2007-08-22 13:46:03 · 3 answers · asked by Anonymous in Mathematics

does the slight depression on the center of the cell help in in any way to do its job?

2007-08-22 13:45:35 · 4 answers · asked by beep_pussycatdolls_fan 1 in Medicine

I need to know something that is catchy and something I can remember on the top of my head.

Someone make something good up.

2007-08-22 13:42:33 · 3 answers · asked by Anonymous in Botany

2007-08-22 13:33:40 · 2 answers · asked by zebbie g 2 in Zoology

2007-08-22 13:30:55 · 3 answers · asked by Ronald B 1 in Mathematics

I did some weird fiddling with math and I got a number such that divided by itself = -1. It is somehow related to i (imaginary). Somebody tell me what's going on?

2007-08-22 13:28:51 · 2 answers · asked by Mitchell 5 in Mathematics

form polygons with integral areas. For example, one could construct a square with an area of 9 sq. units and a cross with an area of 5 sq. units. Can you use all 12 matches to form the perimeter of a polygon with an area of exactly 4 sq. units? The entire length of each match must be used.

2007-08-22 13:27:36 · 1 answers · asked by Anonymous in Geography

A rocket is shot straight into the air at an initial velocity of 96 ft./sec. The height of the rocket after x seconds is represented by the formula h = 96x – 16x2. What is the maximum height the rocket reaches?
6 ft.
144 ft.
180 ft.
240 ft.

2007-08-22 13:26:24 · 4 answers · asked by Anonymous in Mathematics

The Valley High School student council is sponsoring a dance. They anticipate that 500 students will attend. The ticket price is $3, and they estimate that for every $.20 increase in ticket price, 25 fewer students will attend. What ticket price will maximize the student council's profit?
$3.25
$3.40
$3.50
$3.80

2007-08-22 13:25:13 · 2 answers · asked by Anonymous in Mathematics

if I bought something for 250.00 plus 8.250 sales tax, whats the total cost I would pay?

2007-08-22 13:25:03 · 3 answers · asked by invalid chromosome 2 in Mathematics

Which equation has the solutions x =1/2 and x =3/4 ?
1. 8x2 + 10x + 3 = 0
2. 8x2 – 10x – 3 = 0
3. 8x2 + 10x – 3 = 0
4. 8x2 – 10x + 3 = 0

2007-08-22 13:24:22 · 1 answers · asked by Anonymous in Mathematics

Power Inverter 12V -220V -6000W .what the transistor or mosfet can it do in Inverter .plese help me fast.

2007-08-22 13:17:02 · 2 answers · asked by Anonymous in Engineering

if there is a big greyish locked box on a person's property on a platform of cement, what is inside the box? i think it is some sort of electrical equipment but i'm not sure. also, how could a person forcibly open one of these? hypothetically of course.

2007-08-22 13:14:56 · 4 answers · asked by Alex 3 in Engineering

Identify the value of the discriminant for the equation 6x2 = 2x – 1.

(A) 28
(B) 24
(C)–22
(d) –20

Which one?

2007-08-22 13:14:41 · 3 answers · asked by Anonymous in Mathematics

while walking by a farmyard filled with chickens and rabbits, a farmer decided to count the heads and feet of his animals. He came up with a sum of 100 (counting both heads and feet). How many of each animal were in the farmyard?

2007-08-22 13:13:53 · 4 answers · asked by Ron 3 in Mathematics

2007-08-22 13:12:26 · 11 answers · asked by Sparky 2 in Geography

I just want an explanation

2007-08-22 13:12:20 · 6 answers · asked by Dopeboy 1 in Chemistry

There is a jar full of nails, i have 50 nails at my disposal, there is no other jar that i can weigh or use. The jar is oddly-shaped, not perfectly symmetrical, it is smaller at the top of the jar and it gets bigger going down... is there any way of using graphs maybe?

2007-08-22 13:10:49 · 6 answers · asked by Alex T 2 in Other - Science

2007-08-22 13:07:39 · 25 answers · asked by Anonymous in Other - Alternative

for algebra 2

I need help with this one also.
3(x-2)= 5(4+x)

2007-08-22 13:04:34 · 5 answers · asked by Anonymous in Mathematics

ok, their are many debates about if we went to the moon or if it was a hoax. well first off a reason to fake it was that the first to the moon would prbly win the cold war and many predicted if we lost the cold war it would be the downfall of the US. also their is a radiation belt that surrounds the earth (Van allen Radiation belt) and protects us from the sun. it will also kill any who pass without proper protection. and at the time of the space race with the current technology we would need 6 feet of lead to protect the space craft (which was not their). another little question is that just a couple of months ago it was announced that we would go back to the moon between 2017 and 2020 by NASA. and if we went to the moon in the 60's and 70's why wait 10 years to go back why dont we use the same space craft. no one died on the trip to the moon. so why not use the same technology, unless the technology didnt exists and we faked it with a couple of cameras. what are your opinions.

2007-08-22 13:03:58 · 17 answers · asked by ant_szeltner 2 in Astronomy & Space

2007-08-22 13:03:31 · 14 answers · asked by Anonymous in Astronomy & Space

Is this an urban legend?
Truth?
Criminal mischeif?
waste of 5 points?

2007-08-22 13:02:21 · 15 answers · asked by Anonymous in Other - Science

2007-08-22 12:58:44 · 4 answers · asked by Anonymous in Weather

here is a mathematical equation, the first to find why 2+2=3 will get 10 pts

A=B A^2=AB < multiply both sides by A
A^2-B^2=AB-B^2 (A+B)(A-B)=B(A-B) ---------------------------- < _Divide by (A-B)
(A-B) <
A+B=B B+B=B 2B=B --------- <__divide by B
B <
2=1 < result
2+2=3
P.S. yes I am allowd to convert A to B beacause A = B. This is actually simple algebra. If at any time you get comfused, get 2 coins, and another 2 coins, and put them together, if you come up with 3 coins, then I want to see the coins your using ;)

2007-08-22 12:56:53 · 9 answers · asked by Anonymous in Mathematics

Given rho = 1.08 [ohm mm^2/m], what is sigma? ____ [m/mm^2/ohm]

how would I do this?? please help, thanks

2007-08-22 12:56:07 · 2 answers · asked by Anonymous in Physics

Im studing for my test but i dont know the awnser to this one

2007-08-22 12:51:59 · 1 answers · asked by Anonymous in Earth Sciences & Geology