Science & Mathematics - 1 January 2007

2007-01-01 10:48:04 · 6 answers · asked by PrincessElmo M 1 in Zoology

5x+7y= 1
4x-2y=16

2007-01-01 10:48:00 · 2 answers · asked by eduardo r 1 in Mathematics

I have a math project due tommarow and wikipedia was no good here!

2007-01-01 10:47:57 · 1 answers · asked by Radicular 2 in Mathematics

Can some1 answer or help me with these problems? I've been struggling with these equations 4 2 weeks now and still cant understand them. These are pratice problems that i have that i need to understand.These all need to be in order pair.


1) 3x - y = 10
-x + y = -4
a (3, -7)
b (-1, 3)
c (3, -1)
d(3, 1)

2) 3x - y = 9
2x + y = 6
a (3,0)
b (3,-18)
c (3,-1)
d (3,1)

3)-3x + y = -4
3x + y = -4
a (-4, 0)
b (4, 0)
c (0, 4)
d (0, -4)

4)2x – y = 4
3x + y = 1
a (1, 2)
b (-2, 1)
c (1, -2)
d (2, 1)

5) x + y = 10
x - y = 8
a (-1,11)
b (1,9)
c (9,1)
d(8,0)

6)3x - y = 9
2x + y = 6
a (3,0)
b (3,-18)
c (3,-1)
d (3,1)

these ones needs 2 be worked out.

7) 2a + 3b = -1
3a + 5b = -2

8)2x + 2y = -14
3x + y = -9

9)2x + 6y = 38
3x - 3y = -3

10)3x + 5y = 1
x + 4y = 5

11)x + y = -4
x - y = 2

12)x + y = 10
y = x + 8

13)3x + y = 5
4x - 7y = -10

14) y - 2x = -5
3y - x =5

2007-01-01 10:47:27 · 6 answers · asked by Anonymous in Mathematics

2007-01-01 10:46:42 · 5 answers · asked by Anonymous in Zoology

2007-01-01 10:46:37 · 3 answers · asked by reesespieces60202 2 in Geography

I admit, I know next to nothing about electricity, thats why im asking this question.

I want to know what is required to "stretch" my AC electricity in my house. I want to take my "true sine wave" coming into my house, and convert it into a "square sine wave" that will give me ability to power more things for less money. I dont know if this will save money, but it should at least in theory work to power things. I got this idea from looking into a RV and their electrical systems, and learned that they have DC to AC converters to power AC appliances. (although most things run off DC, like a laptop, and in your house you use a AC to DC adapter to power your laptop, cell phone etc.) so you can eliminate the AC to DC adapter for many things in a RV. But the (cheaper) DC - AC adapters also have some unique properties, like giving a "square" sine wave, which messes up digital clocks, breadmakers. - Can I save electricity /money by converting from true to square sine waves in my house?

2007-01-01 10:45:29 · 3 answers · asked by WindowsY2K 1 in Physics

...ok the question says..." If all you have if a 7 min. hour glass and an 11 min. hour glass how can you cook eggs for 15 min.?"

2007-01-01 10:44:45 · 6 answers · asked by alexis g. 1 in Mathematics

The USDA suggests that refrigerators maintain a maximum temperature of 40 degrees F. Of course you want a minimum temperature of about 33, since you don't want your food freezing in there.

The USDA suggests a temperature of 0 degrees F for freezers. Since meat and other items freeze solid at 32 degrees F, what can happen to foods that are frozen in the range between 0 degrees F and 30 degrees F?

I ask because my freezer can only go as low as 15 degrees F, and sometimes creeps up to 28 degrees or so.

To be clear: What happens to the food that is frozen, but is at a temperature between 0 degrees F and 30 degrees F? Bacterial action? Off flavors? Off textures and colors? Any health risks, or just less shelf life?

Thank you.

2007-01-01 10:43:02 · 1 answers · asked by Sean S 2 in Biology

If you use an analog radio frequency adjuster on a radio (the one that is actually a dial or a wheel, and is not digital) and move through all of the AM frequencies that are not used you end up hearing a lot of very different sounding interference and noise. Some of them have a thump-thump-thump and another has a shimmy-shimmy-shwaaa and yet another is just kwisshhshhiwahshsh.

So my question is, where do these sounds come from, and why are they different on the different frequencies? If you listen to FM it's all the same universal static at any frequency that is unused. What makes AM different from this?

2007-01-01 10:40:52 · 4 answers · asked by opticalnoise 4 in Other - Science

So for my science fair project, I did what shape of balloon would travel further, the long and skinny kind you can use to make into animals, or the regular round type. Because of the way they're shaped, I thought that the long and skinny ones would go further. Well, we put the same number of pumps into each balloon, 10, and know it's close to the same amount because we used a balloon pump. But the round ones went the furthest, their distances varying from 10"1' to 10"11' . The long and skinny ones went from 5"8' to 9"2'. What causes this, assuming it relies only on the shape of the balloon and not other factors?
So basically, why do regular balloons travel longer than the long and skinny ones.

2007-01-01 10:40:50 · 3 answers · asked by Briar 4 in Physics

I found what I thought was a mushroom growing in my back yard. It starts out like a white ball in the soil, then it breaks open and orange spongey like stalks grown out, and the inside is clear slimy stuff. But the stalks are all connected, they are not individual. I will try and take a picture tomorrow in the daylight. Does this sound familiar to anyone? I just don't want my kids or my dog to get hold of this if it is poison.

2007-01-01 10:40:31 · 4 answers · asked by jonja91 1 in Botany

Why isn't it winter? It is supposed to be in the 50s all this week, even getting to near 60! To me, this is insane. Where did the cold weather go? I would love to have the weather Denver is having move its way here to the east coast.

2007-01-01 10:38:46 · 28 answers · asked by RegularMan99 2 in Weather

5x+7y=1
4x-2y=16

2007-01-01 10:37:02 · 4 answers · asked by eduardo r 1 in Mathematics

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

2007-01-01 10:35:57 · 7 answers · asked by eduardo r 1 in Mathematics

8x-1=4y
4x=1=3y

2007-01-01 10:34:53 · 3 answers · asked by eduardo r 1 in Mathematics

I need help with the following multiple choice questions, your help is greatly appreciated.

After 32 days, 5 milligrams of an 80-milligram sample of a radioactive isotope remains unchanged. What is the half-life of this element?

1) 8 days
2) 2 days
3) 16 days
4) 4 days

What is the total mass of 222Rn remaining in an original 160-milligram sample of 222Rn after 19.1 days?

1) 2.5 mg
2) 5.0 mg
3) 10. mg
4) 20. mg

Which element forms an ion that is larger than its atom?

1) aluminum
2) chlorine
3) magnesium
4) sodium

Which element is so active chemically that it occurs naturally only in compounds?

1) potassium
2) silver
3) copper
4) sulfur

2007-01-01 10:34:24 · 3 answers · asked by anonydipity_09 3 in Chemistry

how does blood control its pH level when it is too alkaline?

2007-01-01 10:33:24 · 6 answers · asked by RT 2 in Medicine

science project due i do i get an elements pen number

2007-01-01 10:28:01 · 2 answers · asked by Anonymous in Mathematics

jon bought a car for $15, 416 three years ago. Today the value has decreased by 55%. What is the value of the car now?

can you gus please explain it to me please, I know its really easy but i just can think right now, and I really want to understand so thanks :D

2007-01-01 10:26:05 · 17 answers · asked by Caroline M 2 in Mathematics

8x-1=4y
4x+1=3y

2007-01-01 10:19:14 · 2 answers · asked by Walter M 1 in Mathematics

2007-01-01 10:18:49 · 13 answers · asked by sportchick359 2 in Mathematics

i'm bad at design, i don't know what engineering degree suits for me.. but i really love drafting..... i need an advice..

2007-01-01 10:17:25 · 8 answers · asked by thirteen 1 in Engineering

2007-01-01 10:16:40 · 9 answers · asked by shabbakat2 1 in Zoology

Why do scientists say that the universe is expanding? How can it be expanding? Just think of it... if the universe is expanding, that implies that it is in something? And if so, what is outside our Universe?

Therefore, why cant it be possible that the universe is infinite not moving but that the substance inside the universe is moving (Galaxies, stars etc in motion) ???

2007-01-01 10:14:55 · 23 answers · asked by Anonymous in Astronomy & Space

y-x-4
-y-x=3

2007-01-01 10:06:29 · 9 answers · asked by Walter M 1 in Mathematics

I need to discuss the strengths and limitations of different epidemiological studies that have been employed to investigate the association between dietary fibre intake and colorectal cancer.

I really need a few pointers!

2007-01-01 10:03:42 · 5 answers · asked by watford_boy21 1 in Medicine

2007-01-01 10:03:29 · 5 answers · asked by Brooklyn Baby 1 in Other - Science

2007-01-01 10:03:26 · 9 answers · asked by Horine D 1 in Mathematics

plus why are companies like nasa are having problems in advancing technolgies for future spacecraft and space stations also why is it going take a couple of centuries for us humans to become a space faring species.

2007-01-01 09:57:14 · 19 answers · asked by regboi45 2 in Astronomy & Space