# Posts by JJ

Total # Posts: 1,045

**Math**

tens digit + ones digit = 11 tens digit = 3 + ones digit t + x = 11 t = 3 + x substitute: 3 + x + x =11 3 + 2x = 11 Solve for x which represents the one's digit. Then find the tens digit.

*February 20, 2013*

**math**

This is a right triangle problem. c^2 = a^2 + b^2 c^2 = 8^2 + 15^2 remember to take the square root in the last step to find c.

*February 20, 2013*

***math***

I answered earlier. Let x = 0 and find y Let y = 0 and find x. Remember the pairs are written (x,y)

*February 20, 2013*

**Applied Calculus**

This is a chain rule. (the derivative of the whole thing times the derivative of what is in the parenth.) first derivative: (1/2)(5) (5t+4)^-1/2 Take the derivative of the above for the second derivative. Take the derivative of that answer again and you will have the 3rd ...

*February 20, 2013*

**OAA math *wolf***

Tell me what you think the answer is...

*February 20, 2013*

**OAA math *wolf***

If x = 0 find y. If y = o find x. That will give you the ordered pairs. Any time you have a MC question, you can check the values in the problem if you are stuck. (x,y) is the correct order in the ordered pairs.

*February 20, 2013*

**Math**

I would say recheck her work since the estimate and actual are so different from each other.

*February 20, 2013*

**Math**

compare y = x with y = mx+b m = slope What number is in front of the "x" in your equation?

*February 20, 2013*

**college algebra**

The best way to do it is using calculus, but you are in college algebra. You are looking for length + width + width = 1000 feet because you don't need any for the river side. L + 2w = 1000 or L = (1000 - 2w) A = lw A = (1000-2w)(w) A = 1000w - 4w^2

*February 20, 2013*

**trigometry**

It is always good to draw a picture. You have a right triangle with hypotenuse of 16. The side opposite the angle that you are looking for is 5. If you take the opp/hypotenuse = sine of the angle 5/16 = sin of angle. You can use your calculator to find the value of the angle. ...

*February 20, 2013*

**Algebra**

Solve for b? add a -1/6 to both sides of the equation. You have to combine -1/6 and -1/3 You need a common denomiator of 6.

*February 20, 2013*

**Applied Calculus**

I agree with your first derivative. Now, start with 10/(7x+10)^2 and take the derivative again. Denom times deriv of numerator = 0 since deriv of 10 = 0 minus the numer time the deriv of the denomin. - 10(2(7x+10)7) this is the chain rule You need to simplify this expression ...

*February 20, 2013*

**Math - Help with radicals please**

It seems that you need a lesson in everything you need to know about radicals. #3 You can't combine radicals unless they are the same like 3x - 2x = 1x So yo have to write 75 xy as 25(3xy) you can take the square root of 25 with the 3xy left under the radical. for 27x^3y ...

*February 20, 2013*

**Math - Help with radicals please**

do you have any idea how to do any of these or where to start??

*February 20, 2013*

**Algebra**

I didn't get A, Did you make a Venn Diagram with two overlapping circles. The 31 goes in the overlap. for band alone subtract the 31 from 89. For the sports alone subtract the 31 from 215. Add up all of the numbers in the 3 parts of the circles and subtract from 464.

*February 20, 2013*

**Math**

Negative signs and subtraction signs are really the same thing. You can write -8 - 6 negative 8 subtract 6 which is the same thing as writing -8 + -6 negative eight plus negative 6. In both cases, you get a -14 as the answer.

*February 20, 2013*

**Math**

17 -12 is a subtraction problem 4w -w is a subtraction problem.

*February 20, 2013*

**Math math**

Do you mean 3 hundred plus 5 tens? 350

*February 20, 2013*

**Math**

a^2 + b^2 = c^2 17^2 + 26^2 = c^2

*February 20, 2013*

**Physics**

12 mg per kg. so multiply 12 times 73 and this gives you the answer in mg. convert to kilograms we know 1000 g = 1 kg we also know 1000 mg = 1 gram

*February 20, 2013*

**CALCULUS**

I will give you a hint. The derivative of e^x is e^x.

*February 20, 2013*

**Math**

See my anwer to the previous question. You should be able to do it.

*February 20, 2013*

**Calculus**

derivative of e^x is e^x Derivative of e^xk is k e^xk Can you finish it from here?

*February 20, 2013*

**chemistry**

You have to find the volume of the block by multiplying L x W x H One you have the volume, you can find the density. density = mass/volume Your answer should be in grams/cm^3

*February 20, 2013*

**World History**

I like your answer. It also lead to the civil war.

*February 20, 2013*

**World History**

Abolition is the elimination of slavery in this country. Think about the significance of no slaves to the plantation owners and about the freedom to the slaves themselves.

*February 20, 2013*

**math**

You have 4 chances out of 7 of getting a blue marble.

*February 20, 2013*

**electronic logic**

You need to look up these systems.

*February 20, 2013*

**algebra 2**

Start by taking the ratio of 800/2000 reduce it to 2/5 or .4 multiply 800 times .4 = 320 next multiply 320 times .4 and continue until you get to the 6th term.

*February 20, 2013*

**Business**

These look pretty obvious to me. For example b - having merchandise in many different sizes and colors will give shoppers more choice which will lead to more sales.

*February 20, 2013*

**algebra**

you need an improper fraction. 5/4 times 28 gives you the exact answer. an estimate is between 28 and 56.

*February 19, 2013*

**US HISTORY**

WHAT WAS THE PANIC OF 1887

*February 19, 2013*

**us history**

what was his war

*February 19, 2013*

**us history**

i still cant find why in their

*February 19, 2013*

**us history**

explain jacksons war on the bank

*February 19, 2013*

**math**

density = mass/volume density = 360g/36 ml

*February 19, 2013*

**algebra**

You solve this by creating a Venn Diagram with 3 intersecting circles. Begin by putting the 4 where the 3 circles intersect. When you are done, add up each part of all of the circles and you should get 70. If you get less than 70 that means customers purchased none of these ...

*February 19, 2013*

**reading**

That is what I think.

*February 19, 2013*

**reading**

Read this carefully and think about what you would do if you were afraid.. He was looking around, then what did he do?

*February 19, 2013*

**math**

log(base 4) 4^6 = x convert to exponents 4^x = 4^6 so x =6 which means the expression = 6

*February 19, 2013*

**math**

You need to get a common denominator of 35. Multiply the top and bottom of 3/5 by 7 and multiply the top and bottom of 4/7 by 5. Then, keep the denominator and subtract the numerators to give you the difference in weights.

*February 19, 2013*

**math**

Divide 24 into 80 to give you the number of packages. You will need to round up to get the correct answer. There will be more than 80 pencils, but the teacher will have to buy that number of packages to be sure to have enough.

*February 19, 2013*

**math**

I answered this in your post below.

*February 19, 2013*

**Statistics**

Population parameter percent of all voters who will vote for the candidate the value of the sample statistic would be 35/150 and this could be used to estimate the population parameter.

*February 19, 2013*

**math**

To write an equation you would write: 88 + box = 97 or 88 = 97 - box

*February 19, 2013*

**math**

Begin by factoring out the common factor of 2. That leaves x^2 + x - 42 Factor this trinomial Looks like you will be dealing with 6, 7. One is positive and the other is negative. Remember that distance cannot be measured as a negative number.

*February 19, 2013*

**Statistic**

You have to find z scores first. 66.2-69.0 then divide by 2.8 77.4 - 69.0 then divide by 2.8 Now, you have to find the area between those two z scores. The empirical rule tells you the % between -3 and 3 standard deviations, between -2 and 2 sds and between -1 and 1 standard ...

*February 19, 2013*

**Math**

When comparing fractions, if the denominators are the same.. the larger numerator gives you the larger fraction.

*February 19, 2013*

**Math**

You have to get a common denomiator first then you can compare the numerators. Try for a denominator of 24. this means that you have to multiply the top and bottom of the 6/8 fraction by 3. And multiply the 1/3 (top and bottom) by 8.

*February 19, 2013*

**Math**

You might want to reduce 2/8 to 1/4 first and 4/6 to 2/3 Now, you are compaing 1/4 and 2/3. Can you do this based on my answers to your other two questions?

*February 19, 2013*

**Math**

I think you are missing your second topping. but, the denominators are the same so you can just compare the numerators. Making a picture sometimes helps.

*February 19, 2013*

**math**

This is an order of operation question. My Dear Aunt Sally. Multiplication and Division are done first Addition and Subtraction are done second. Otherwise work from left to right. 3 + 7 - 7 + 3 - 3 x 3 3 + 7 - 7 + 3 - 9 Now just combine from left to right.

*February 19, 2013*

**Please help quick**

You are working with the sum of two squares that you cannot factor and the difference of 2 squares that can be factored. Perhaps your teacher just wants you to show that one factorization.

*February 19, 2013*

**Algebra**

Did you start the problem? You have to begin by factoring.

*February 19, 2013*

**Algebra**

The numerator, you have to factor by grouping. Group: (3a^2 + 6ab) + (-a -2b) Take out the common factor in each group and then you should see two identical factors. Write that factor down once and your second factor is what is left over (actually, what you factored out from ...

*February 19, 2013*

**science**

I am thinking burning propane in a gas heater. It give off energy. The others seem to be absorbing energy.

*February 19, 2013*

**math**

a = 3 b = 29 c = -8.5 You can find the quadratic by a google search. It is sort of hard to write it here.. but here it is in words minus b plus or minus the square root of b-squared -4ac all over 2a. This will give you 2 values for x.

*February 19, 2013*

**Math**

I would starb by getting rid of the decimals. Multiply the second equation by 10 5x + 2y = 30 x + y = 9 multiply the bottom equation by -2 5x + 2y = 30 -2x -2y = -18 Add the two equations to get 3x = 12 so x = 4. Find y by substituting into one of the original equations. then ...

*February 19, 2013*

**math**

sample sapce r w r g w r w g g r g w You have 1 chance out of 6 to get rg in that order.

*February 19, 2013*

**MATHS!**

swimming has 4 choices cycling has 3 choices running has 2 choices 4 x 3 x 2 = 24 possible routines.

*February 19, 2013*

**Statistics**

You have to find the z-score for each of the given values. 11.97 - 12 divided by 0.015 will give you a z. Do the same for 11.99. You have to use a z-table or a calculator to find the the probability between those to z-scores. Do the same for part b.

*February 19, 2013*

**algebra**

a ratio is just a fraction so it is 22/26 but then reduce your fractions.

*February 19, 2013*

**College Algebra**

$400,440 + 845x =1200x $400,440 + 845x = 1199.99x x = # of TVs to get the answer to the second part compare your answer from the 1st to the 2nd.

*February 18, 2013*

**Math**

You can graph the line by solving for y: -4y = -3x -8 y = 3/4x + 2 (divided everything by -4) If x = 0 you should get 2 for y if x = 4 you should get 3 + 2 = 5 for y Now, you have two points (0,2) and (4,5) You always should have one more point to be sure your line is correct...

*February 18, 2013*

**Math**

I think you mean that you have 3 raised to a -1 power divided by 3^3. What you do with negative powers is just moved them up or down in the fraction to make the power positive. so, you can move the 3 to the denominator as 3^1 power now combine the 1st power with the 3rd power ...

*February 18, 2013*

**Chemistry**

atomic mass unit this is the mass we see listed for the elements in the Periodic Table.

*February 18, 2013*

**Math**

We are double and triple posting because the web site is acting up a little.

*February 18, 2013*

**Math**

148 drachma is 1 dollar ?? drachma is 10 dollars would you get 1480 drachma Then just divide by the 3 items to get the max per item.

*February 18, 2013*

**MaTH**

First you have to put your line into y = mx + b format. 9x - 6y = -3 -6y = -9x -3 y = 9/6 x - 3 y = 3/2 x - 3 Parallel lines have the same slope. m represents you slope. Perpendicular lines have slopes that are negative reciprocals of each. flip the fraction and include the ...

*February 18, 2013*

**Mth**

To find the slope of the line, you have to rewrite the equation to solve for y. y = mx + b the m = the slope and the b = y-intercept. 2x -4y = 2 subtract 2x from both sides then divide each term by -4. What you have in front of the x will be your slope. do you need more help ...

*February 18, 2013*

**math**

y = 3/4 (0) + 2 = 0 + 2

*February 18, 2013*

**math**

There a few ways to do this problem. You could chose values for x and then solve for y. If x = 0, you would have -4y = -8 so y = 2 You need 3 points to graph the line. Try x = 4 and then find y. another way is to put the equation into the form of y = mx + b -4y = -3x - 8 y = 3...

*February 18, 2013*

**math**

Is the ? divided by?? If so you are dividing a trinomial by a monomial you just divide each term of the trinomial by the monomial -9x^3 divided by -3x 3x^2 divided by -3x -15x divided by -3x Remember to divide the coefficients (numbers out in front) Then for the x's with ...

*February 18, 2013*

**chemistry**

If you increase the N2 or H2 concentrations that is going to force the production of NH3 If you increase the temperature, to maintain equilibrium heat has to be given off. Which means more NH3 If you add pressure you need fewer molecules which again causes the production of ...

*February 18, 2013*

**Algebra 2**

let n = 1 which gives you 3(1) + 4 Let n = 2 gives you 3(2)^2 + 4 Continue like this until you have 6 terms.

*February 18, 2013*

**Finite Math**

An easy way to do this is to choose a term of 1 year and $1 amount. You can then use the formulas. For the first one: P(1+r/2)^2 let P = 1 and r = .068 Do you know how to set up the second one?

*February 18, 2013*

**math**

1. to order the fractions you have to have the same denominator. Use a denomiator of 24. So that means for 3/4, you have to multiply the numerator and the denominator by 6 to get 18/24. Do something similar to the other two fractions. Then you can compare them easily. 2. You ...

*February 18, 2013*

**Earth Science**

I bet you can find it by doing a google search.

*February 18, 2013*

**Applied Calculus**

The rule is the denominator times the derivative of the numerator minus the numerator times the derivative of the denominator AND then put this answer over the denominator squared. The deriv. of the numerator is 3x^2 and the deriv of the denom. is 2x Can you finish from here?

*February 18, 2013*

**Math**

Here is another way to think about it. You could write the equation of the line first in y = mx+b You substitue: 4 = 2(-5) + b 4 +10 = b 14 = b y = 2x + 14 Now let x = some values and solve for y and you will have the points you need to graph the line.

*February 18, 2013*

**Statistics**

I just did the test using a TI-83 calculator. I got a t=-2.60 with a p=.026 If you are doing the test... since .026 is smaller than .05, you can reject the null hypothesis. Which means they did gain more weight with B.

*February 18, 2013*

**math**

Substitute 5670 for P. and .035 for r. add 1 to .035/2 Square that answer and then multipl by 5670

*February 18, 2013*

**Science-Physics**

Initial speed plus the acceleration times the time. 6.61 m/s + 3.46 m/s/s times 3.92 s 6.61 m/s + ____ m/s (fillin the blank with 3.46 times 3.92). The same principle applies, but you will be multiplyint by -3.46 which will result in a decrease in the speed.

*February 18, 2013*

**algebra**

If he is trying to make 15% from 15% then he doesn't need any water at all. He can just use the sulfuric acid directly. If they want 10 liters, then he needs 10 liters of the sulfuric acid. But.. is this really the question or did you mistype something?

*February 18, 2013*

**College Algebra**

I know how to do this with calculus, but algebraically it starts the same way. L + 2W = 800 L = 800 - 2w A = LW A= (800-2w)w A = 800w - 2w^2 Take the derivative: 800 -4w 800 -4w = 0 to find max. 800 = 4w 200 =w l = 400

*February 18, 2013*

**physics**

d = rt 18 = (51.6)(t) Solve for t.

*February 18, 2013*

**physics**

a =v/t a = 80/20 = 4 m/sec/sec north

*February 18, 2013*

**math**

The second equation can be rewritten as log(x-2y) = 2^5 The first equation is more complicated because you have different bases. You need to chane base 4 to base 2 by using the rule that allows for base changes. Once you do this, you can use the Law of Logs to combine the left...

*February 17, 2013*

**english**

Bias means it is one-sided, unfair and trying to make you agree with their opinion. Unbiased means there is no slant to it and they just are reporting facts and you can't really tell the writers position.

*February 17, 2013*

**English**

They don't sound correct either.

*February 16, 2013*

**Algebra**

Solve for y in each case. Be sure to write the equations in the forms of y = mx+b m = slope. If the slopes are the same, then the lines are parallel.

*February 16, 2013*

**college algebra**

(3,1) is the vertex of the parabola. (1,9) and (5,9) y = ax^2 + bx + c Substitue in the point (3,1) 1 = a(9) +b(3) +c Do the same for (1,9) and then again for (5,9) You will have 3 equations and 3 variables. Solve for a, b, c. There is also a formula to find the equation using...

*February 16, 2013*

**Math**

Is the calculus? If so, take the derivative of y which would be 4x^3 - 3x^2-2x -1 Let x =1 to find the slope 4-3-2-1 = m = -2 find the value of y when x = 1 You will then have the slope and a point to use to find the equation using y=mx+b

*February 16, 2013*

**math**

I agree with A, B,C. is D -3.744 with nothing after it. If so, it is rational.

*February 15, 2013*

**Math algebra**

length is L = W + 8 Area is length times width. 560 = (w+8)w 560 = w^2 + 8w 0 = w^2 + 8w - 560 factor to solve for w. (discard negative values) Then substitute to find L. Be sure to check by multiplying to be sure you get the 560 in^2.

*February 15, 2013*

**algebra story problem**

I just answered this one above for someone that posted as "college student"

*February 15, 2013*

**math algebra**

length is twice the width L = 2W area is length times width. 72 = (2w(w) 72 = 2w^2 divide both sides by 2 to get 36 and then take the square root of 36 to find "w". double that value to find the length. Check by multiplying l times w to see if you get 72.

*February 15, 2013*

**statistics**

14 x 13 x 12 x 11x 10 This is the counting principle. This Assumes choosing: ABCDE is different from ACDEB If you really want a combination you can use: 14! divided by the product of 5!times 9! 5! means 5x4x3x2x1 there will be fewer combinations because ABCDE is the same as ...

*February 15, 2013*

**Math**

Take the 20th root of each side then subtract 1 from both sides to solve for g.

*February 15, 2013*

**math**

AP Calculus.

*February 14, 2013*