Thursday

October 27, 2016
Total # Posts: 385

**Physics**

In a hydroelectric dam, water falls 26.0 m and then spins a turbine to generate electricity. What is ∆U of 1.0 kg of water? Suppose the dam is 80% efficient at converting the water's potential energy to electrical energy. How many kilograms of water must pass through...

*November 30, 2009*

**Algebra word problem**

A retailer of DVD players knows that at a price of q dollars per player, he can sell (900 – 3q) players per month. Write a polynomial, in function notation, that represents the monthly income from the sale of DVD players.

*November 29, 2009*

**communications**

The electronic version is just an on-line, web version of the same ad that is in print, such as in a newspaper.

*November 21, 2009*

**Math**

The perimeter of a rectangle is 34 feet and the area measures 60 square feet. What are the length and width of the rectangle? (Hint: Use the equations : perimeter = times the sum of the length and the width area = length times width)

*November 21, 2009*

**Algebra 1**

Marcus and Allen are playing Rock/Paper/Scissors. The first one to one 10 times does not have to do the dishes. The score is now 9 to 7 in favor of Marcus. If ties are ignored and not counted, what is the probabilty Marcus will not have to do the dishes? Express your answer as...

*November 16, 2009*

**Pre Calc**

I get where a comes from. Is the answer 53/-610? It doesn't seem right.

*November 15, 2009*

**Pre Calc**

Write a quartic function that has roots that are 3+5i, -4 and 7 and f(-3)=53. I have tried it a bunch of times and can't seem to get it. (x-3+5i)(x-3-5i)(x+4)(x-7) I multiplied them together x^4-9x^3+24x^2+66x-952 I was a little unsure what f(-3)=53 means. I thought I ...

*November 15, 2009*

**Pre Calc (For Reiny)**

Thanks so much your method worked perfectly! My solution was: the remaining zeros were 5+2i, 3, and -4 I have one question that's bugging me though, why is it that synthetic division did not work for me? I thought that long division and synthetic division were both ...

*November 15, 2009*

**Pre Calc**

I am familiar with this type of problem but can't seem to get the right answer. Use the given zero to find the remaining zeros of each function f(x)=x^4-9x^3+7x^2-91x-348,zero 5-2i I normally would use synthetic division with the root 5-2i bringing it down to x^3. Then ...

*November 13, 2009*

**Pre-Calc Can't find where I went wrong**

I tried to solve for H in the volume equation. so, 2=3.14(r^2)H divide 2 by 3.14=.64 .64=r^2H .64/r^2=H Not sure where to go from here

*November 13, 2009*

**Pre-Calc help can't find the volume**

How do I get the volume?

*November 13, 2009*

**Pre-Calc**

Is the volume 2L? How can I solve for diameter if I don't have the height?

*November 13, 2009*

**Pre-Calc**

Starkist tuna company will package tuna fish in 2-L cans. Find the radius and the height of the cans if the cans have a surface area which is less that 980 cm^2. I have no idea how to go about this, it seems like geometry to me. Can you give me some help? Please.

*November 13, 2009*

**Algebra 1**

x^2 + 16=0 Solve by graphing

*November 12, 2009*

**Pre- Algebra**

-6x-15>57 +15 +15 -6x>72 Divide both sides by -6 And switch sign because dividing the variable by a negative x<-12

*November 12, 2009*

**Algebra 1**

Thanks And I think you answered my question last time i posted, so thanks for keep on rollin' :)

*November 12, 2009*

**Algebra 1**

On a multiple choice test with 10 questions and 5 choices, A,B,C,D,E, for each questions, what are the odds of guessing on all 10 questions and getting 100%. State your answer as a common fraction. Thanks -Zach

*November 12, 2009*

**Algebra 1**

Thanks

*November 5, 2009*

**Algebra 1**

Mary's class took two tests last week. 80% of the class passed the math test, 90% of the class passed the English test, and 72% of the class passed both. What is the probablility that a randomly selected student in Mary's class failed both tests? Express your answer as...

*November 5, 2009*

**math**

3x^2-15x+18=0 -18 3x^2-15x=-18 square root 3x-15x=4.2426406871192851464050661726291 divide by 3 x-15x=1.4142165323730950488016887242097 divide by -15 x+x=-0.094280904158206336596779248280647 -x x=-0.094280904158206336596779248280647x

*November 5, 2009*

**Physics-revision**

those funky è letters are supposed to be theta. The funky ì is mu.

*October 28, 2009*

**Physics**

Okay, here is a solution. Not sure if it's the best one, but it seems to work. D = drag force D = (1/4)Av^2 v is terminal velocity A = 1.80m * 0.300m F(net) = D since there is no acceleration m*g*sinè - ì(kinetic)*m*g*cosè = (1/4)Av^2 solve for v (your...

*October 28, 2009*

**Biology**

How can I make a 3D model of a bone cell?

*October 18, 2009*

**math**

flexible rounding to estimate the answer 622+377= 84-27=

*September 21, 2009*

**gr 4 math**

we are working on number charts, I need to know what position pattrens means and what number pattren means? whats the difference?

*September 14, 2009*

**math**

A magician has 3 more red hats than black hats and 4 fewer purple hats than black hats and has 14 hatsin all. How many hats of each color does he have. Show how you got the answer.

*September 14, 2009*

**Chemistry**

The greater electronegativity difference bewteen two atoms bonded together, the greater the bond's percentage of ______ a. ionic character b. nonpolar character c.metallic character d.electron sharing Thank you!!!!

*May 31, 2009*

**Chemistry**

What does a covalent bond consist of? Thanks!

*May 30, 2009*

**Chemistry**

Which stage of ionization usually produces more ions?

*May 27, 2009*

**spanish**

dailey routine

*May 3, 2009*

**Organic Chemistry**

Does anyone know where I might find a step-by-step reaction mechanism for a polymer condensation reaction involving Hexamethylenediamine with Adipoyl Chloride (thus synthesizing Nylon 66)? If not, can anyone help list the steps that take place and why? Any help would be ...

*April 26, 2009*

**Science**

Predict what would happen to a reptile body temperature if the outdoor temperature increases by 10c.

*March 16, 2009*

**english root word**

factum - how do I use in a sentence. If it's a root word, are there any words with factum in them? I can't find any.

*February 17, 2009*

**Algebra1**

Hey, this helped me with my extra credit. Thanks :-)

*February 17, 2009*

**6th grade Social Studies**

your mom

*December 15, 2008*

**Chemistry**

How Many Molecules are contained in 0.25 moles of Fe?

*December 11, 2008*

**Dynamath for October**

iZachIsCool don't get it is hard I have to find the answers I am a teacher and I need them now I am at school and when I looked I did not get any answers can u tell me 😳

*September 29, 2008*

**Chemistry**

ΔT = T(mix) - T(initial) And the equations is: HCl(aq)+ NaOH(aq) => NaCl(aq) + H2O(l) And T(mix) = 37 C 50.0 mL of 2.0M HCl = 23.7 C 50.0 mL of 2.0M NaOH = 23.5 C How do I find T(initial), do I just use their averages? Thanks

*September 29, 2008*

**Algebra 1 **

How many quarts of pure pineapple juice should Theo add to a 20% pineapple drink to create 5 quarts of 50% of pineapple juice mixture?

*September 23, 2008*

**Chemistry**

Calculate the DELTA H(rxn), DELTA S(rxn), DELTA S(universe), DELTA G(rxn). For each system below indicate whether DELTA S and DELTA H are positive or negative. Then indicate if the reaction is entropy driven, enthalpy driven or neither. C3H8(g) + 2O2(g) => 3CO2(g) + 4H2O(g)

*September 19, 2008*

**biology**

what are the forms in which carbon is found in the ocveans?

*September 16, 2008*

**Alegbra**

Show that the distance between the points (x,y) and the line Ax + By + C = 0 is: D = (Ax + By + C) / sqrt(A^2 + B^2) So, would you start out by multiplying sqrt (A^2 + B^2) to both sides and then it would become: sqrt (A^2 + B^2)D = Ax + By + C Then square both sides, D^2(A^2...

*September 8, 2008*

**Ged Test Results**

test scoring

*July 29, 2008*

**earth**

A word for ater that flows downhillafter it rains 6 letters

*June 2, 2008*

**english**

i need a sentence with the word "justice"

*May 21, 2008*

**math**

a farmer must get a mouse, a cat and a block of cheese across the river. He will make three trips. He can not leave the cat and mouse together on either side and he can not leave the mouse and cheese together on either side. How will he get them across the river?

*May 19, 2008*

**Economics 101**

Hey guys my Econ final is on Tuesday and I could use some help. These are 4 example questions true/false with explanation needed. 1. A monopolist will produce less and charge a higher price than a perfectly competitive industry. 2. Regardless of the type of price control, if ...

*May 4, 2008*

**English**

What are the differences between utopia and dystopia? What are some current real world references to utopia and dystopia?

*April 25, 2008*

**Physics**

A steel beam is used in the construction of a skyscraper. By what fraction L/L0 does the length of the beam increase when the temperature changes from that on a cold winter day (-20°F) to that on a summer day (+108°F)?

*April 17, 2008*

**PHYSICS**

Oil is flowing with a speed of 1.30 m/s through a pipeline with a radius of 0.315 m. How many gallons of oil (1 gal = 3.79 10-3m3) flow in one day?

*April 14, 2008*

**English expression**

The first one is correct. Because you don't have candy in a plate, you have it on a plate, and candy even though we know it is plural you would use "is"

*April 2, 2008*

**college algebra**

Let f(x)= x^5/120 - x^3/6 + x Find the local minima and maxima, then determine where the function is decreasing and increasing. Basically, I just need to know how to type this correctly in my calculator so I can get the right minima and maxima. I had: local minima: f(-1.59)=-1...

*April 2, 2008*

**math**

Determine whether the functions are even, odd, or neither. (a) f(x) = x²/√x²+ 1 (b) g(x) = x^3 - √ x- 7

*April 2, 2008*

**french**

Only with etre and reflexive verbs, do the subjects agree.

*April 2, 2008*

**college algebra**

Ok I started by diving by 12 to get x² + y² + 3/2y = 0 then x² + y² +3/2 + ____ = 0 + ____ then (3/2)² = 3/4 (3/4)² = 9/16 and got the equation x² + y² + (3/2)y + 9/16 = 0 + 9/16 here is where I am confused x² + [y+(3/4)]² = (3...

*April 2, 2008*

**college algebra**

Would you start by dividing everything by 6? then after that I am confused

*April 2, 2008*

**college algebra**

Identify the center and radius of the circles represented by the following questions (a) 3x² - √3x+3y²-y+ 1/12=0 (b) 12x² + 12y²+42y=0

*April 2, 2008*

**chem**

A sample of hydrogen has a volume of 1100 mL when the temperature is -0.899999999999999 degC and the pressure is 0.888 atm. What will be the volume of the gas at STP?

*March 28, 2008*

**chem**

A sample of fluorine has a volume of 3.6 L when the temperature is 112.3 degC and the pressure is 922 torr. What will be the volume when the pressure is 88.48 kPa and the temperature is 140.4 degC?

*March 28, 2008*

**chemistry**

A sample of chlorine has a volume of 2.5 L when the temperature is 84.1 degC. Assuming that the pressure is constant, at what temperature will the volume be 1750 mL? (Express your answer in Kelvins.)

*March 28, 2008*

**Physics**

During a tennis serve, a racket is given an angular acceleration of magnitude 155 rad/s2. At the top of the serve, the racket has an angular speed of 13 rad/s. If the distance between the top of the racket and the shoulder is 1.5 m, find the magnitude of the total acceleration...

*March 26, 2008*

**Physics**

You are installing a new spark plug in your car, and the manual specifies that it be tightened to a torque that has a magnitude of 45 N·m. Using the data in the drawing, determine the magnitude F of the force that you must exert on the wrench. Lenght of the wrench is ....

*March 24, 2008*

**Physics**

An automatic drier spins wet clothes at an angular speed of 4.8 rad/s. Starting from rest, the drier reaches its operating speed with an average angular acceleration of 3.6 rad/s2. How long does it take the drier to come up to speed?

*March 6, 2008*

**Physics**

A motorcycle has a constant speed of 24.0 m/s as it passes over the top of a hill whose radius of curvature is 129 m. The mass of the motorcycle and driver is 330 kg. Find the magnitude of (a) the centripetal force and (b) the normal force that acts on the cycle. I found the ...

*March 5, 2008*

**Physics**

The earth rotates once per day about an axis passing through the north and south poles, an axis that is perpendicular to the plane of the equator. Assuming the earth is a sphere with a radius of 6.38 106 m, determine the speed and centripetal acceleration of a person situated...

*March 3, 2008*

**Physics**

A cyclist approaches the bottom of a gradual hill at a speed of 20 m/s. The hill is 4.4 m high, and the cyclist estimates that she is going fast enough to coast up and over it without peddling. Ignoring air resistance and friction, find the speed at which the cyclist crests ...

*February 25, 2008*

**Physics**

A cyclist approaches the bottom of a gradual hill at a speed of 20 m/s. The hill is 4.4 m high, and the cyclist estimates that she is going fast enough to coast up and over it without peddling. Ignoring air resistance and friction, find the speed at which the cyclist crests ...

*February 25, 2008*

**Physics**

Batman (mass = 90 kg) jumps straight down from a bridge into a boat (mass = 530 kg) in which a criminal is fleeing. The velocity of the boat is initially +20 m/s. What is the velocity of the boat after Batman lands in it?

*February 25, 2008*

**physics**

A 0.052-kg arrow is fired horizontally. The bowstring exerts an average force of 80 N on the arrow over a distance of 0.75 m. With what speed does the arrow leave the bow?

*February 25, 2008*

**algebra**

p=2l+2w solve for l

*February 23, 2008*

**algebra**

p=2l+2w forl

*February 22, 2008*

**physics**

A person pulls a toboggan for a distance of 40.0 m along the snow with a rope directed 15.0° above the snow. The tension in the rope is 69.0 N. (a) How much work is done on the toboggan by the tension force? (b) How much work is done if the same tension is directed ...

*February 19, 2008*

**Physics**

A 97.0-kg person stands on a scale in an elevator. What is the apparent weight when the elevator is (a) accelerating upward with an acceleration of 1.70 m/s2, (b) moving upward at a constant speed, and (c) accelerating downward with an acceleration of 1.80 m/s2?

*February 18, 2008*

**electromagnetism**

Why does the speed of wind have no affect on a homemade electromagnetic generator attatched to a windmill? I did an expiriment using a windmill and altered the wind speed 3-11mph. There was no change in the amount of amps genrerated. Are my results just wrong or is there a ...

*February 11, 2008*

**Mathematics!**

She would have to be 2.22 repeating for them to have a tie. Yoku actually runs 8 yards in ten seconds

*January 8, 2008*

**Math -**

PLEASE HELP ME FIGURE THIS PROBLEM! Solve equation and check the solution -3(r+5) = 3(r - 1)__________________

*November 12, 2007*

**languege arts**

rentcuy

*November 4, 2007*

**math**

I have 5 pieces each is a triangle and they are supposed to somehow form a large triangle. Everyone has tried and we can't figure it out. I see lots of solutions online for 7 piece tangrams but nothing for a 5 piece. Thank you Zach I suspect there are 180 solutions to this...

*August 10, 2007*

**algebra**

evaluate the numerical expression 2 (14-7) + 5 Is the 2 supposed to be an exponent of something? Where does it go?

*May 16, 2007*

**Physical Science**

What are the 4 nuclear forces? Out of the 4 which one is the strongest and which one is the weakest? Thanks http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html THANK YOU As a side note, these are not nuclear forces. They are the four fundamental forces in nature, ...

*April 11, 2007*

**drivers ed**

It is a crossword puzzle nine letters long. Vital to vehicle saftey

*March 14, 2007*

** Why dogs are better than Cats!**

shouldn't we just get over it and just finish this stupid debate

*November 24, 2006*

**Algebra**

-6h + 4 - 3 + h = 11 4-3-11=6h-h -10=5h -2=h

*September 21, 2006*

**unscramble**

afsedrniru

*September 6, 2006*

**Science guys :)**

hey guys a got a few problems i need help with im really desperate for help they're due soon online :( 1.Suppose that a constant current of 89 mA flows in a conductor. Find the absolute value of the total charge that passes through the conductor in 3 minute(s). Charge = ...

*August 31, 2005*