# Posts by Charlie

Total # Posts: 468

**algebra 1**

Re type your question, I don't understand what you are trying to find.

*April 2, 2012*

**algebra**

Mult 1st eq by 3; x-2y+3z = 0 Mult 2nd eq by 4: 2x - 3y + 4z = 1 Add 2nd and 3rd: -4y+5z = 2 Mut 1st by 2: 2x-4y + 6z = 0 Add that answer and 3rd eq: -5y + 7z = 1 5(-4y + 5z = 2) + -4(-5y + 7z = 1) -20y + 25z = 10 + 20y - 28z = -4 -3z =6 z = -2 Sub into the 1st eq: x - 2y -6 =...

*April 2, 2012*

**algebra**

x=1, y = -3, z=-2

*April 2, 2012*

**math**

The larger x values are to the right

*April 2, 2012*

**Intermediate Algebra**

(1/8 )(16/81)(216/125) (2/81)(216/125) (2/3)(8/125) 16/375

*April 2, 2012*

**Physics**

Part of a single rectangular loop of wire with dimensions .35 m by .75 m (.35 is the height and .75 is the length) is situated inside a region of uniform magnetic field of 0.395 T. The total resistance of the loop is 0.690 Ω. Calculate the force required to pull the loop ...

*March 31, 2012*

**physics**

A light spring having a force constant of 110 is used to pull a 15.0 sled on a horizontal frictionless ice rink. The sled has an acceleration of 1.60 ? [2/27/12 9:41:56 PM] Matt Yeager: By how much does the spring stretch if it pulls on the sled at 29.0 above the ...

*February 27, 2012*

**geometry**

true

*February 19, 2012*

**math**

If the height of a cylinder is made nine times longer, how many times the volume of the original figure is the volume of the new figure?

*February 16, 2012*

**algebra**

2012 with a power of 2012

*January 26, 2012*

**Chem II**

1605kJ

*January 18, 2012*

**Physics**

You pull on a rope that is attached to a box. The rope makes an angle of 25 degrees with the ground. You are pulling the box at a constant velocity. The force you are pulling with is 78N. The box weighs 25N. You pull the box a displacement of +16m. What is the work done by you...

*January 5, 2012*

**HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!**

At what level, or what kind of figure skating team? You can just google this; I did and some I found are: Team USA (Olympic team), Talbot Figure Skating Team (for Talbot county Maryland), The Diamond Blades, Dartmouth University Figure Skating Team, and the Achilles Edge ...

*January 5, 2012*

**Aviation**

Do you mean how hard you have to push the pedal? If so, it's hard to say. Cars may or may not have power brakes, airplanes may or may not have something similar. I'd think it also depends on how fast the plane is going, and crosswinds, etc.

*January 5, 2012*

**algebra**

can you place 44 coins in 10 containers evenly and not have the same amount of coins in each container

*December 1, 2011*

**statistics**

can you place 44 coins in 10 containers and have them distributed evenly

*November 18, 2011*

**social studies**

idk im asking u omg

*November 7, 2011*

**4th grade Math**

9Times1equals9

*November 3, 2011*

**trigonometry**

The side of a lake has a uniform angle of elevation of 15 degrees 30 feet. How far up the side of the lake does the water rise if the height of the lake increases by 7.3 feet during flood season.

*October 13, 2011*

**math**

write the expression for a number used as a factor seventeen times being multiplied by a number used as a factor fourteen times. then write the product as one power

*October 12, 2011*

**applied math**

An operating log indicates that the average flow through a pump for ten hours is 285 gallons per minute. The following week, the same output is measured as 340 gallons per minute. What is the percent change?

*September 26, 2011*

**Physics**

Thanks very much

*September 25, 2011*

**Physics**

Hi Would someone be able to confirm that the following equation wil give the fall time for an object falling under gravity ignoring air resistance: T= sq root of 2h/g where h is fall height and g is accel due to local value for gravity. A derivation from a more usual equation ...

*September 25, 2011*

**Geometry**

If PT=3x-4 and QS=4x-3 how do I solve

*September 16, 2011*

**fourth grade math**

round this number to the nearest thousand 409,614

*September 14, 2011*

**anoymous**

more it it thani

*September 9, 2011*

**Math**

What does KAPS mean in Math?

*August 18, 2011*

**statistics**

27. Consider the following hypothesis test. H0: µ = 15 Ha: µ ≠ 15 A sample of 10 gives a sample mean of 8.9 and population variance of 9. Consider the following data drawn from a normally distributed population: 4, 8, 12, 11, 14, 6, 12, 8, 9, 5, α = 0.01...

*August 8, 2011*

**Physics**

Help me find c.

*July 26, 2011*

**Physics**

The radius of the Earth is 6.38 x(10^6)m. How far (path length) does a point on the equator move if the Earth rotates... a. 20 degrees b. 20 radians c. 20 revolutions

*July 26, 2011*

**Algebra**

Thanx...Ms. Sue... I just wanted to know.

*July 26, 2011*

**Algebra**

How did you get the second one with 1/4?

*July 26, 2011*

**statistics**

A population of 200 voters contains 52 Republicans, 128 Democrats, and 20 independents and members of other parties. A simple random sample of 20 voters will be drawn from this population. The expected number of Republicans in the sample is? and The standard error of the ...

*July 26, 2011*

**chemistry**

iF 50.0 g of iron (II) carbonate react completely with hydrochloric acid, how many grams of carbon dioxide gas may be produced?

*July 3, 2011*

**Chemistry**

Give the following reaction,find the mass of oxygen required to produce 13grams of CO2; C3H8+5O2--->3CO2 + 4H2O

*June 15, 2011*

**Math**

What percentage of the data falls outside 1 standard deviation of the mean?

*June 7, 2011*

**Algerbra 1**

A(1,4), (6,8) Round to the nearest tenth

*May 24, 2011*

**chemistry**

in the reaction 2Na + Cl2 --> 2NaCl how many grams of NaCl are produced when 25 g. of sodium reacts completely to form NaCl?

*May 17, 2011*

**chemistry**

I have two solutions of 0.1 Molar. A solution of magnesium chloride and a solution of potassium chloride. I thought that the 0.1 M solution of magnesium chloride would conduct electricity better than a 0.1 M solution of potassium chloride. I did a lab in my chemistry class but...

*May 11, 2011*

**Social Studies**

Mandate of Heaven

*April 25, 2011*

**Social Studies**

What are the 5 things that every business needs to succeed?

*April 3, 2011*

**statistics**

Three students take equivalent stress tests. Which is the highest relative score? a. A score of 144 on a test with a mean of 128 and a standard deviation of 34. b. A score of 90 on a test with a mean of 86 and a standard deviation of 18. c. A score of 18 on a test with a mean ...

*April 3, 2011*

**statistics**

Three students take equivalent stress tests. Which is the highest relative score? a. A score of 144 on a test with a mean of 128 and a standard deviation of 34. b. A score of 90 on a test with a mean of 86 and a standard deviation of 18. c. A score of 18 on a test with a mean ...

*April 3, 2011*

**physics**

1.when white light is shone on red ink dried on a glass plate, the color that is transmitted is red. But the color that is reflected is not red. what is it? 2.a spotlight is coated so that it won't transmit blue from its white hot filament. what color is the emerging beam ...

*March 31, 2011*

**physics**

1.calculate th speed of waves in water that are 0.4m apart and have a frequency of 2hz? 2. sound waves travel at approximately 340m/s what is the wavelength of a sound with a frequency of 20Hz? what is the wavelength of a sound with a frequency of 20 kHz? 3.a bat flying in a ...

*March 31, 2011*

**Chemistry**

You mix 1.00 L of 2.00 M BaCl2 with 1.00 L of 2.00 M AgNO3. What compounds remain in solution, and what are their concentrations?

*March 29, 2011*

**algebra**

how do you solve for y in the equation -1/y=-0.25x^2-3.5

*March 22, 2011*

**algebra**

how do you solve for y in the equation 1/y=(1/3)x^3-(253/12)

*March 22, 2011*

**algebra**

how do you solve for y in the equation 1/y=-0.5x^(-2)-0.5

*March 22, 2011*

**Traveling(saving money)**

the cheapest pleese does it depend on when your going if so then for india in dec. and for england then july

*February 23, 2011*

**Traveling(saving money)**

how much are plane tickets to: india england

*February 23, 2011*

**physics**

so does the ball clear by 1 m or does the ball not clear the crossbar and misses it by 1 m.

*February 22, 2011*

**physics**

trying to win the superbowl, a placekicker attempts a field goal from 45 m away. when kicked, the ball leaves the ground with a speed of 22m/s at an angle of 50 degrees above the horizontal. what can you say about the ball when it reaches the crossbar that is 3.0m above the ...

*February 22, 2011*

**physics**

sorry that was 188 that i got

*February 22, 2011*

**math**

How do i find the extrema (local maximum and minimum) by using the first derivative of: x^3-(3/2)x^2?

*February 16, 2011*

**physics**

while watching ocean waves at the dock of the bay. otis notices that 10 waves pass beneath him in 30 seconds. he also notices that the crests of succesive waves exactly coincide with the posts that are 5 meters apart. what are the period frequency wavelength and speed of the ...

*February 11, 2011*

**physics**

the lowest frequency we can hear is about 20hz. calculate the wavelength associated with this frequency for sound that travels at 340m/s. how long is this in feet.

*February 11, 2011*

**physics**

calculate the speed of waves in a puddle that are 0.15m apart and made by tapping the water surface twice each second

*February 11, 2011*

**physics**

a nurse counts 76 beats in one minute. what are the period and frequency of the hearts oscillations?

*February 11, 2011*

**math**

In gift wrapping department, a customer can choose from x different papers, y different ribbons, and z different greeting cards. There are 160 different paper, ribbon, and greeting card combinations possible. List three of the possible combinations. What forumula are used? Don...

*February 2, 2011*

**math**

write the 100-complement of 40

*January 20, 2011*

**chemistry**

Lewis diagram for NO3- and NH4+

*January 10, 2011*

**physics**

calculate the period of a pendulum if the length of the pendulum is o.8m. what is the period if the angular deflection is 30 degrees? 45 degrees?

*January 8, 2011*

**physics**

calculate the amount of heat energy required to raise the temperature of a 5kg block of solid platinum from 0 degrees celsius to 25 degrees celsius. the specific heat of platinum is 133j/kg k. how much heat energy is required to raise 5kg of water by the same amount? the ...

*January 8, 2011*

**9th grade science**

A landslide may be caused when friction is ______ by moisture

*January 4, 2011*

**9th grade science**

A landslide may be caused when friction is ______ by moisture

*December 16, 2010*

**AP Physics**

A cylindrical container of radius 20 cm contains water of height of 3 m. Two meters down from the water level there is a hole of 0.5 cm in radius. Find the velocity and volume flow rate of water leaving the hole. Where does it strike the ground?

*November 29, 2010*

**math**

need help please. thanks evaluate and simplify. (8x/y) for x=10 and y=2

*November 14, 2010*

**math**

Tell which real number corresponds to the situation: During a month, a person withdraws $350. what is the corresponding # for this sentence?

*November 14, 2010*

**science-6th grade**

what is between the helium particles in a helium filled balloon?

*November 5, 2010*

**College Physics**

A mass of 0.4 kg, hanging from a spring with a spring constant of 80 N/m, is set into an up-and-down simple harmonic motion. What is the velocity of the mass when at its maximum displacement of 0.1 m?

*October 24, 2010*

**College Physics**

A multiple loop configuration is rotating at 60 Hz in a magnetic field of 0.12 T. The coil has an area of 0.0052 m2. How many coil loops are required to produce a maximum voltage difference of 170 V?

*October 24, 2010*

**Chemistry**

I conducted a simple titration experiment and i need to write how and why are the results reproducible can some one help me in answering this. Thankyou C.

*October 17, 2010*

**Science**

I have my results from a simple titration experiment (sodium carbonate against hydrochloric acid) Average titre of 53.27 cm3 which i am happy with but how can i reason that my results are accurate?

*October 15, 2010*

**Periodic Table**

Hello all, how does the periodic table determine the type of bonding of compounds Cheers Charlie.

*October 13, 2010*

**Science (Bonding)**

thankyou, srajmcgin

*October 13, 2010*

**Physics, relativity**

Thanks Drwls, but that's the press release I spotted the error in. I think!

*October 11, 2010*

**Physics, relativity**

I read this in a write-up of an experiment using atomic clocks: To reveal these effects, required the use of highly accurate atomic clocks, calibrated to check that they are perfectly in sync with each other – ticking down the nanoseconds (that's one billionth of a ...

*October 11, 2010*

**college chemistry**

whats is the boiling point of a solution composed of 17.6g of urea in (NH2)2CO in .300 kg of water

*October 4, 2010*

**physics**

the passenger's weight is ALWAYS mass x acceleration. Can you work out the acceleration at all 3 stages? The mass of the person is the same for all 3.

*September 28, 2010*

**11th grade**

Suppose you surveyed 50 students and 34 said that they approve of how the president is doing. Construct 90%, 95%, and 99% confidence intervals for the true proportion of students in your school who approve of how the president is doing. Be sure to specifically calculate the ...

*September 12, 2010*

**college physics**

A box on a frictionless horizontal surface is pulled by a tension of 42.4N directed at 45 degrees above the horizontal. what is the work done on the box as it moves 2.50 meters along the surface?

*September 11, 2010*

**college physics**

A box on a frictionless surface is pulled back a distance x into a spring with spring constant k and released. What is the formula for the kinetic energy of the box after it leaves the spring?

*September 11, 2010*

**College Physics**

A 50 kg skater moving at 5 m/s over frictionless ice grabs a rope stretched out 10m from a post and perpendicular to her path. She then moves in circles, spiraling inward as the rope wraps around the post. How fast is she moving when she is 2 meters from the post?

*September 11, 2010*

**8th grade Math**

3p - 1.5

*September 9, 2010*

**math**

let me retype the question. Sorry for the scribble. 1/2 X 1/2 answer in simplest form. must show work. thanks

*August 29, 2010*

**math**

desperately seeking help. work must be shown. answer must be in simplest form. Thanks 1 1 _ X _ 2 2

*August 29, 2010*

**mat115**

There are multiple choices for the answer to this problem. They are a) 1/5 b) undefined c) 5 d) 5/7 Thanks again for both of your help

*August 29, 2010*

**mat115**

Sorry Reiny, The question is 11-6/7-7 I thought the answer was 5/0= undefined. Can you please let me know if I am wrong and show the work so I can further understand your answer. Thanks Reiny

*August 29, 2010*

**Math**

Thanks Reiny, Yes, I spotted that it dosen't work for any run of primes, but it does up to 9. I'm afraid i don't really follow your explanation! An answer for dummies maybe? Charlie

*July 30, 2010*

**Math**

I have to find the relationship between these sequences, and express a generality. Could you help please. 1 + 3 + 5 + 3 + 1 = 3^2 + 2^2 1 + 3 + 5 + 7 + 9 + 7 + 5+ 3 + 1 = 5^2 + 4^2 1 + 3 + 1 = 2^2 + 1^2 I'm thinking sum of consecutive primes can be expressed in squares? ...

*July 30, 2010*

**Physics**

It's too hard. You should give up now

*July 6, 2010*

**gen.science**

A compound containing 3 atoms of carbon and 8 atoms of hydrogen is combined in a reaction with oxygen molecules. The two end products of this equation are carbon dioxide and water. Which chemical or element will have the largest number of moecules?

*June 21, 2010*

**chemistry**

What was the purpose of the phenolphthalein?

*June 1, 2010*

**Math algebra**

I'm reposting this, because Mathmate's answer hasn't directed me to the WHY? part of the question. Any prompts appreciated. The product of any two (whole) numbers each of which leave a remainder of 1 on dividing by 7, also leaves a remainder of 1 on dividing by 7...

*May 3, 2010*

**math**

I have this question to work on, and I don't know where to start investigating the answer: The product of any two (whole) numbers each of which leave a remainder of 1 on dividing by 7, also leaves a remainder of 1 on dividing by 7. Why? I THINK that I can see a quadratic ...

*May 2, 2010*

**physics**

If the angular quantities θ,ω,α were specified in terms of degrees rather than radians, how would the kinematics equations for uniformly accelerated rotational motion have to be altered?

*April 11, 2010*

**Physics**

Ok thanks, but why isn't this true for an arm or leg?

*February 3, 2010*

**Physics**

Why is the CM of a 1.00m length of pipe at its midpoint, whereas this is not true for your arm or leg?

*February 3, 2010*

**Math**

I need to figure out what a deposit of 3500 a month, with 9 percent intrest compounded monthly, would be in 6 years. Any help would be greatly appreciated.

*January 13, 2010*