Saturday

August 27, 2016
Total # Posts: 2,447

**Math**

When -24 + 7i is converted to the exponential form re^{i \theta}, what is cos(theta)?
*August 23, 2016*

**Math**

one person takes up about 2.5 square feet of space. use this value to estimate how many people can fit in an area that is 120 feet wide and 300 feet long.
*August 15, 2016*

**Math precalculus**

Let z and w be complex numbers such that |z| = |w| = 1 and zw does not equal -1. Prove that (z + w) / (zw + 1) is a real number. I have tried to rationalize the denominator and I got (z^2*w-z*w^2) / (zw)^2-1 but that got me nowhere. Can someone please help me!!!
*August 15, 2016*

**Math**

Never mind I got it
*August 5, 2016*

**Math**

Convert ( 4, -pi/6) from polar coordinates to rectangular coordinates. I got sqrt 12, -2 as my answer but it said this was wrong. I checked multiple times and I don't see where I messed up
*August 5, 2016*

**Math**

Whoops bad math:) Thanks!
*August 3, 2016*

**Math**

It says that -2/3 is wrong
*August 3, 2016*

**Math**

The graph of r = 7/ (3 cos(theta) + 2 sin(theta)) is a line. What is the slope of the line? How do you do this!!!
*August 3, 2016*

**Maths**

Prove That If the equation x^2+ax+b=0 and cx^2+2ax-3b=0 have a common root then b=5a^2(c-2)/(c+3)^2
*July 24, 2016*

**Math**

Please Help A body consists of a solid hemisphere of radius r joined to a right circular cone of base radius r and perpendicular height h. The plane surfaces of the cone and hemisphere coincide and both solids are made of the same material. Show that the centre of gravity of ...
*July 24, 2016*

**physics **

A girl sees her image in a shiny glass sphere tree ornament that has a diameter of 18 cm. The image is upright and is located 2.9 cm behind the surface of the ornament. How far from the ornament is the child located? The child is located cm in front of the ornament.
*July 18, 2016*

**physics **

A power transmission line is made of copper that is 1.8 cm in diameter. If the resistivity of copper is 1.725 10-8 Ω · m, find the resistance of 7 mi of the line.
*July 7, 2016*

**physics **

A copper wire that has a diameter of 2.9 mm carries a current of 39.0 A. Assuming that each copper atom contributes one free electron to the metal, find the drift velocity of the electrons in the wire. The molar mass of copper is 63.5 g/mol and the density of copper is 8.95 g/...
*July 6, 2016*

**Physics **

During a thunderstorm, a lightning bolt carries current between a cloud and the ground below. If a lightning bolt transports a total charge of 80 C in 0.001 s, what is the magnitude of the average current? A
*July 6, 2016*

**Physics**

A stone is dropped from the root of a building. A person in the building observes that the stone crosses his window that is 2 meters tall in a time of 0.2 second. How far is the roof from the top of the window?
*June 30, 2016*

**physics**

A cyclist is on a rolling stationary trainer pedaling such that his wheels are traveling at 30 km/h. He has an unfortunate incident and ends up falling over 90° on his side onto a large patch of ice. Given the cyclist and bicycle have an 4.5 kg*m^2, find the angular ...
*June 30, 2016*

**Math**

bob is a genius!!!
*May 31, 2016*

**physics **

A dolphin wants to swim directly back to its home bay, which is 0.800 km due west. It can swim at a speed of 3.58 m/s relative to the water, but a uniform water current flows with speed 2.95 m/s in the southeast direction.
*May 29, 2016*

**Math**

The heights of Japanese maple trees are normally distributed with a mean of 6 meters and a standard deviation of 0.2 meter. What percent of Japanese maple trees are between 5.5 meters and 6.7 meters tall?
*May 25, 2016*

**math**

-9?
*May 20, 2016*

**MATH FACTORING**

10x^2+615x+20125 FACTOR PLS
*May 20, 2016*

**Pre- algrebra**

2. D 3. B Combine like terms..
*May 20, 2016*

**word problem math**

3
*May 17, 2016*

**Math**

What's nine minus three divided by a third plus one
*May 15, 2016*

**Math**

Same person i know the answer to the first part is 1260. I don't know how many teams will have Alex.
*May 12, 2016*

**Math**

In how many ways can a team of 5 players and a coach be chosen from 10 players and 5 coaches? How many of these teams will contain Alex, one of the player?
*May 12, 2016*

**Math**

In how many ways can a committee of 12 people, of which 5 must be in the 21−30 age group, 4 must be in the 31−40 age group and 3 must be in the 41−50 age group, be chosen if there are 6 people of each age group?
*May 12, 2016*

**Math**

In a card game player get at the start 2 green cards, 3 blue cards, 4 red cards, and 3 yellow cards. In how many ways can the player get cards at the start if this card game has 7 green, 7 blue, 10 red and 10 yellow cards?
*May 12, 2016*

**Math **

John has travel 630 miles. The car does 27miles per gallon. The car has a 9 gallon tank. How many times will he have to fill up.
*May 12, 2016*

**Exponential Modeling**

Suppose a tortoise is 2000 feet from the ocean. Each day the tortoise travels one-half of the remaining distance to the ocean. Use this information to: Compute the remaining distance to the ocean after 4 days of travel.
*May 1, 2016*

**Exponential Modeling**

Atmospheric pressure decreases by about 12% for every kilometer you climb. The pressure at sea level is about 1013 atmospheres. How many atmospheres of pressure will you feel at 8.848 km?
*May 1, 2016*

**Exponential Modeling**

A species of frog’s population grows 24% every year. Suppose 100 frogs are released into a pond. How many frogs will there be in 5 years?
*April 30, 2016*

**math**

The Davidson family wants to expand its rectangular patio, which currently measures 15 ft by 12 ft. They want to extend the length and width the same amount to increase the total area of the patio by 160 ft2. Which quadratic equation best models the situation? A = lw (15)(12...
*April 29, 2016*

**World History**

Can somebody check over my answers my answers are : B;C;B;A;D;C;A;B;D;C;A;B;B;B;C;D;A;A;B;C;… C;D;1. Trench warfare caused the immobilization of troops on the (1 point)Western Front.Middle Eastern desert.Eastern Front.mountains in Russia.2. After the war, Britain ruled ...
*April 20, 2016*

**Social Studies**

Actually I like C
*April 15, 2016*

**Social Studies**

The Northwest Ordinance established all of the following, except rules for territories to become states. denying slavery to new states formed from the territory. preventing new states from entering the United States. the right to education (------my choice
*April 15, 2016*

**Physics**

A geostationary satellite orbits the Earth in such a manner that it is always directly above the same point on the equator as the Earth rotates. Assuming that this orbit is circular, what is its radius? (The mass of the Earth is approximately 5.97 × 1024 kg and the ...
*April 15, 2016*

**chemistry**

how many protons and electrons are in 7.4 grams of hydrogen?
*April 13, 2016*

** Statistics**

If a normally distributed group of test scores have a mean of 76 and a standard deviation of 10. Find the probability that student will earn a grade between 65 and 85
*April 9, 2016*

**Math**

Let $f(x) = \dfrac{2-3x}{5-2x}$. For what value of $a$ is $f(a) = 3$? Thanks!
*April 3, 2016*

**Math**

Let f(x) = 2-3x/5-2x. For what value of a is f(a) = 3?
*April 3, 2016*

**Math**

210 litres divided by 2 then divided by 2.5l per minute =42
*March 30, 2016*

**Math**

Given the points (A) 0,0 (B) 4,3 (C) 2,9 what is the measure of angle ABC
*March 30, 2016*

**Math**

If a square is 8.4 feet on each side. How many square feet is it
*March 28, 2016*

**Chemistry **

In a 1.0× 10–2 M solution of CH3NH3Br(aq), identify the relative molar amounts of these species. H2O, OH-, CH3NH3+, CH3NH2, H3O+, Br-, HBr
*March 28, 2016*

**reading comprehension**

C. JIM IS PENNYS GRANDFATHER
*March 21, 2016*

**Physics**

A 40.0 ohm resistor, 20.0 ohm resistor, and a 10.0 ohm resistor are connected in series across a 220-V supply. Which resistor is the warmest? a. 40.0 ohm b. 20.0 ohm c. 10.0 ohm d. they are all the same
*March 18, 2016*

**Math**

An object is launched at 9.8 meters per second from a 73.5-meter tall platform. The object's height s (in meters) after t seconds is given by the equation s(t)= -4.9t(-4.9t) - 9.8t = 73.5. When does the object strike the ground? I can't figure out how to factor it ...
*March 11, 2016*

**Math**

A woman bought some 13 cent stamps and some 8 cent stamps at the posg office. She spent exactly 1 dollar. How many of each stamp could she have bought?
*March 11, 2016*

**Math**

If sales tax in a specific county is 6.5%, what is the total price paid on a purchase of $156.00.
*March 8, 2016*

**CHEMISTRY HELP**

assume that 13.5g of AL react with excess HCl according to the following balanced equation, at STP: 2Al(s) + 6HCl(aq) ---> 2AlCl3 + 3H2(g) how mang liters of H2 at STP are produced?
*March 6, 2016*

**Physics**

Thank you!
*March 3, 2016*

**Physics**

A circuit consists of a 10 ohm resistor in series with 3 identical batteries each with an emf = 1.0V and internal resistance of 5 ohms. a) find potential difference between the terminals b) potential difference across the 10 ohm resistor c) power dissipated in resistor
*March 3, 2016*

**Science**

Calculate the amount of heat required to completely convert 1kg of water at 0°C to the boiling point at 100°C?
*February 23, 2016*

**algebra**

A hotel swimming pool measures 25 m by 9m. The hotel manager wants to put a 3m wide deck around the pool. Calculate the area of the deck
*February 19, 2016*

**Calculus**

Find the length of the entire perimeter of the region inside r=5sin(theta) but outside r=1. 1=5sin(theta) theta=arcsin(1/5) r'=5cos(theta) I tried the integral between arcsin(1/5) and pi-arcsin(1/5) of (((5sin(theta))^2+(5cos(theta))^2))^1/2 which gives me 13.694 Webworks...
*February 19, 2016*

**Algebra: Check Answer**

Okay, Thanks!
*February 16, 2016*

**Algebra: Check Answer**

one more: 3x^2 - 147 = 0 a) -47, 49 b) -7, 7 ~~MY ANSWER~~ c) -square root 7 , square root 7
*February 16, 2016*

**Algebra: Check Answer**

x^2 - 81 = 0 a) -square root 9 , square root 9 b) -81 , 81 c) -9 , 9 ~~ MY ANSWER ~~ d) no real solutions
*February 16, 2016*

**Trig.**

If TanTheta= -65/72 and the terminal side of theta lies in Quadrant II use a pythagorean identity to find sec theta.
*February 13, 2016*

**Physics**

A bullet of mass 3.9 g was fired at a stationary ball of lead. The head on impact moved the 10 kg ball at a velocity of .3703 m/s. If energy losses due to heat and internal energy are ignored. What was the speed of the bullet? a)370 b)950 c)549 d)975
*February 13, 2016*

**Physics**

A bullet of mass 3.9 g was fired at a stationary ball of lead. The head on impact moved the 10 kg ball at a velocity of .3703 m/s. If energy losses due to heat and internal energy are ignored. What was the speed of the bullet?
*February 12, 2016*

**math**

Write the equation of horizontal line passing trough the point (5, 2).
*February 12, 2016*

**English**

Okay, will do. I'll be back. Thanks!
*February 11, 2016*

**English**

Yes!
*February 11, 2016*

**English**

In The Importance of Being Earnest, Jack and Algernon clearly have a preoccupation with food. Discuss how food serves as a symbol for obedience to impulse and the pursuit of pleasure. How does this symbol help Oscar Wilde to comment on and satirize society?
*February 11, 2016*

**Geometry**

Could you please explain the difference between B, longer base of a trapezoid and b, base in geometry?
*February 11, 2016*

**Geometry**

Oh so we add 3X And the 3X to get 6X for EF ?
*February 10, 2016*

**Geometry**

For 2 similar triangles ABC and DEF, the scale factor of ABC to DEF is 2:3. If AB=2(BC) and DE=3(BC), what is EF?
*February 10, 2016*

**math**

If 210 people say pizza is their favorite food,how many people were surveyed using the graph if 42% chose pizza, 33% chose hotdogs, and 25% chose pasta?
*February 8, 2016*

**Math **

Bett, Cathy, Isabel, Lani and Ursula run an 800-meter race. Betty beat Cathy by 7 meters. Alma finished 12 meters behind Lani. Bettty finished 5 meters ahead of Ursula but 3 meters behind Lani. Isabel finished halfway between the first and last person. In what order did they ...
*February 2, 2016*

**Chemistry**

* 1" x 1" x 1/8"
*February 1, 2016*

**Chemistry**

A 1" x 1" 1/8" copper ingot has a density of 8.94 g/mL. 25 pellets were obtained from the ingot. Explain what would be the density of each pellet. I went ahead and found the mass of the ingot which is 1.1175g but I'm still stumped on what to do from there.
*February 1, 2016*

**algebra**

find the zeroes and state the multiplicity of multiple zeroes y=(x+1)^2 (x-1) (x-2) I know that x=-1 x=1 x=2 I dont know how to find the multiplicities
*January 30, 2016*

**Physics**

A thin metallic spherical shell of radius .5m has a total charge of 8 μC uniformly distributed on it. At the center of the shell is placed a point charge of 4 μC. What is the electric field at a distance of .15 m from the center of the spherical shell? I know that EA...
*January 27, 2016*

**Physics**

the pressure at a point below a point below the surface of the sea is caused by both the height of the water above that and the air pressure on the surface of the sea. if the diver reaches a depth of 20m below the surface on the surface of the sea Calculate The total pressure ...
*January 26, 2016*

**Physics**

A proton is released from rest inside a region of constant, uniform electric field E1 pointing due North. 14.8 seconds after it is released, the electric field instantaneously changes to a constant, uniform electric field E2 pointing due South. 8.07 seconds after the field ...
*January 23, 2016*

**Algebra**

could you at least tell me the steps i would take to finish it up
*January 21, 2016*

**Algebra**

Write y=-2/5x-3 in standard form using integers. 2x+5y=-15 2x+y=-3 2x+5y=-3 x+y=-15
*January 21, 2016*

**Math**

Write each fraction as a percent rounded to the nearest percent 1/3
*January 15, 2016*

**Maths**

There are 20 questions in a test. Faye answers 17 correctly. a. What fraction of questions does faye answer correctly? b. What percentage of the questions does Faye answer correctly?
*January 14, 2016*

**Maths**

Write < or > for each pair of numbers -6.9 is < or > -6.85 -7.02 is < or > -7.2
*January 14, 2016*

**Maths**

Work out 0.14 x 0.87 0.52 x 6.57 0.36 x 5.24
*January 14, 2016*

**Maths**

Round 4.389 to 2 decimal places.
*January 14, 2016*

**Maths**

Write the decimals in ascending order. 5.78, 5.08, 5.8, 5.287, 5.078
*January 14, 2016*

**Maths**

A figure skater scores 74.92 in her first skate and 144.19 in her second skate. What is the total score?
*January 14, 2016*

**Maths**

John has a piece of wood 2.4m lon. He cuts of a piece 0.8.4m long. How long is the remaining piece?
*January 14, 2016*

**Math**

It is 780 km from Lethbridge to Fort McLeod. One plane leaves from Lethbridge going 200 km/h. A second plane leaves from Fort McLeod going 300 km/h. When do they pass in the sky?
*January 12, 2016*

**Algebra (Urgent)**

What is an equation in slope intercept form for the line that passes through the points (1,3) and (3,1)?
*January 7, 2016*

**Physics**

The force on a .4 kg cannon ball in the barrel when fired at t=0 seconds is given by F= 1000- 5 * 10^4t. The acceleration of the ball is 0 as it leaves the barrel The total impulse in Newton seconds on the ball during the .02 seconds it's in the barrel would be
*January 5, 2016*

**Language Art's**

that's not really helpful for students who need at least a starter on their questions
*January 5, 2016*

**Algebra**

What is the ninth term of the arithmetic sequence defined by the rule A(n)=-14+(n-1)(2) A)232 B)230 C)2 D)4 Thanks
*December 22, 2015*

**Mathematics**

Using quotient rule find dy/dx of: y=(4+x)/(cos(x)) and find the equation of the normal to the curve y=(4+x)/(cos(x)) at the pint where x=0 Use y=mx+c form
*December 14, 2015*

**Mathematics**

Solve: (2+x)(-sinx)
*December 14, 2015*

**physics **

Jake needs to catch 1 10 pound fish to last 5 days. He catches 2 3.33 pound fish, 1 2.11 pound, and 1 1 pound fish. How long will he survive with that amount of food?
*December 13, 2015*

**stat**

A poll of 1000 registered voters reveals that 480 of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, do the data provide sufficient evidence to conclude that the percentage of voters who prefer the Democratic candidate...
*December 13, 2015*

**stat**

A poll of 1000 registered voters reveals that 480 of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, do the data provide sufficient evidence to conclude that the percentage of voters who prefer the Democratic candidate...
*December 13, 2015*

**Math cosine law**

I just finished the calculations and it gave me an answer of 160 m
*December 9, 2015*

**Math cosine law**

A golfer hits a tee shot on a 325 m long straight golf hole. The ball is hooked (hit at an angle of 18 degrees to the left. The ball lands 185 m from the tee. How far is the ball from the hole ?
*December 9, 2015*

**Dynamics**

A ball weighing .2 Lbs. is dropped out the window of a pickup truck (approx. 5 ft?) moving horizontally at 45mph. If e (coefficient of restitution) between the ball and the ground is equal to .6, find the height of the ball's first bounce and the horizontal distance it ...
*December 8, 2015*