Thursday

May 28, 2015

May 28, 2015

Total # Posts: 31,422

**math**

You just gave an example. Go ask 20 visitors their age. That's probably not a good example, since it's fairly hard to pick truly random people. But, you might count the number of people entering or leaving in a certain time period, and tracking that value over the ...
*March 25, 2015*

**Algebra (Math)**

these are just vertical or horizontal lines. clearly, the first set of equations intersect at (2,-3) The second intersect where y=2 so, plugging that into the second equation, x+2*2=10 x = 6 and they intersect at (6,2) Having said that, and solved the systems, go ahead and ...
*March 25, 2015*

**Math**

note that each gallon of cleaning solution treats 8 pails of water. So, now how many pails, to use up 16 gallons of solution?
*March 25, 2015*

**Pre-Calculus**

(s+6)^2 = 3/4 s+6 = ±√3/2 s = -6±√3/2 This is where it helps to keep track of things s = -6 ± (√3/2) NOT s = (-6±√3)/2 so, putting it all over 2, s = (-12±√3)/2
*March 25, 2015*

**math**

take a look at the number line. 29035 is to the right of 0. -1349 is to the left of 0. so, the distance between them (the difference, in other words) is 29035 - (-1349) = 29035+1349 = 30384
*March 25, 2015*

**Algebra**

that's only about 6.5 meters on a side. So, probably not elephants, nor mice. What smallish animals do you know?
*March 25, 2015*

**math**

total change: 35 degrees total time: 7 hours so, average change is 35°/7hr = 5°/hr
*March 25, 2015*

**math**

you have difficulty adding and subtracting numbers?
*March 25, 2015*

**PreCalculus**

since the area of a circular segment is a = 1/2 r^2 (θ-sinθ) you need θ such that cos(θ/2) = x/8 so, you need to solve 1/2 * 64 (2*arccos(x/8)-sin(2*arccos(x/8))) = 64π/3 x = 2.12 inches ---------------------------------- 3.5 mi/hr = 0.058 mi/min If ...
*March 24, 2015*

**math**

42 feet
*March 24, 2015*

**math**

If the 2nd piece is x, then x+3.57 + x + x+2.97 = 15
*March 24, 2015*

**geometry**

c = 2πr, so r = C/2π v = 4/3 π r^3 = 4/3 π (C/2π)^3 = 4/3 π C^3/8π^3 = 1/6 C^3/π^2
*March 24, 2015*

**math**

how about a 7-layer pyramid, with each layer 1 block wider than the layer above? Start with just 1 block on top.
*March 24, 2015*

**math**

x+y = 90
*March 24, 2015*

**geometry**

it's a frustrum of a cone.
*March 24, 2015*

**Solid Mensuration**

recall the volume of a spherical cap, as found here: http://en.wikipedia.org/wiki/Spherical_cap Now just plug in your numbers.
*March 24, 2015*

**Solid mensuration**

just look up the formula for the volume of a spherical cap of radius r and height h. Then plug in your numbers. Hint: find the volume of the smaller cap and subtract it from the whole ball. See here: http://en.wikipedia.org/wiki/Spherical_cap
*March 24, 2015*

**math**

recall that BC-AB < AC < BC+AB
*March 24, 2015*

**PHYSICS -urgent**

horizontal is constant at 92 m/s vertical is 9.8*19.9 so, (d) is just the resultant speed s, where s^2 = h^2 + v^2
*March 24, 2015*

**Implicit Differentiation (Please HELP)**

x^2 - 4y^2 + 1292 = 0 2x - 8yy' = 0 y' = x/4y You have x and y, so y' = 1/4 the line is thus y-8 = 1/4 (x-8) see at http://www.wolframalpha.com/input/?i=plot+x%5E2+%E2%88%92+4y%5E2+%2B+192+%3D+0%2C+y+%3D+1%2F4+%28x-8%29%2B8
*March 24, 2015*

**algebra**

√18/(√18-3) recall that (a-b)(a+b) = a^2-b^2. So, multiply by the "conjugate" to get √18(√18+3) / (√18-3)(√18+3) = (18+3√18)/(18-9) = (18+3√18)/9 = (6+√18)/3 = 3+√2 (4-3√2)^2 = 4^2 - 2(4)(3√2...
*March 24, 2015*

**Math**

any two points can be joined by a single line. In this case it's y-52488 = ((-393216-52488)/(-4-3))(x-3) There are many power functions which can go through any two points.
*March 24, 2015*

**math**

which is greater 8/4 or 5/3? and what do you mean by "over" when talking about paints?
*March 24, 2015*

**Math**

original size: w(w+2) after folding, the box is (w-12)(w+2-12)6 = 4050 w = 37 so, the original piece was 37x39
*March 24, 2015*

**Math Check**

How about -10x + 2y = 48 -5x - 3/2 y = -9 or, even better, -5x + y = 24 -10x - 3y = -18 or, getting rid of all the useless minus signs, 5x - y = -24 10x + 3y = 18
*March 24, 2015*

**math**

so, no effort on your part, eh?
*March 24, 2015*

**math**

a(x) domain: same as that of f range: [0,225) since (-15,2] = (-15,0]U[0,2] square those and you have [0,225)U[0,4] What do you get for b & c?
*March 24, 2015*

**Math Help!!!**

That's better.
*March 24, 2015*

**Math Help!!!**

#4: try again the others look good.
*March 24, 2015*

**Math**

Start with the whole amount, then subtract what was used. The result is what was left: 1 - 1/4 - x = 3/8 x = 3/8 for the cookies why did you use 3/8 - 1/4? 3/8 is how much she had left, and 1/4 was for the cake. How does that tell you anything about the cookies?
*March 24, 2015*

**Math**

Looks more like A to me. You noted the constant ratio, but that is a mark of a GP, not an AP. If you truly have no idea, you clearly need to review what it means to be a geometric or arithmetic sequence. It's annoying when someone comes asking for help, saying that they ...
*March 24, 2015*

**Math, Algebra**

You did not come up with an equation. You have an expression, and it does not provide a value for x. d = s + 3/8 s = f - 3/8 so, d = f - 3/8 + 3/8 = f the dog weighs the same as the ferret, or 1/2 lb must all be babies, eh? Or maybe small plush toys.
*March 24, 2015*

**Math**

well, 987*7 = 6909 = 11*628 + 1 not sure what you mean by inverse, but x=7 is a solution to the equation.
*March 24, 2015*

**Physics**

2.2 m/s is an angular speed of 2.2/35π = 0.02 rad/s so, its angular acceleration is (.02rad/s)/(15s) = 0.00133 rad/s^2 I expect you can find the other one.
*March 24, 2015*

**maths**

dice is already plural. No such word as dices. well, the chance of any one die's being even or odd is 1/2 So, the chance of all three being even or all odd is (1/2)^3, since the events are independent.
*March 24, 2015*

**math**

if x of 2%, then the rest (120-x) is 21%. So, .02x + .21(120-x) = .07*120
*March 24, 2015*

**Math, Algebra**

The question was to find the length of A and B together. a+b = 2b+b = 3b = 3(c + 1/12) = 3(1/6 + 1/12) = 3(3/12) = 3(1/4) = 3/4
*March 24, 2015*

**geometry**

if triangle has side t and square has side s, then 3t = 4s t/s = 4/3
*March 24, 2015*

**stuff**

Sometimes it takes a while for someone to get around to a question. If you open one of your questions, then click on the link for your name, it will show all your posts, even ones that have been pushed down the list. Then you can check to see what has or has not been attended to.
*March 24, 2015*

**Math, Algebra**

x(1 - 1/4)(2/5)*6 = 4320 x = 2400
*March 24, 2015*

**7th grade math**

Looks good to me
*March 24, 2015*

**physics**

since h(t) = vt - 4.9t^2, the vertex is at t = v/9.8 so, v(v/9.8) - 4.9(v/9.8)^2 = 50 v = 31.305 m/s Now you can find how long it was in the air. Namely, twice as long as it took to reach its max height.
*March 24, 2015*

**Math**

x - x/2 - (x/2)(3/4) - 3/4 = 0 x = 6 so, he spent 3 hours on the drums.
*March 24, 2015*

**math**

y = -5/3 x - 7/3 5(x1) = -7 So, now you have m,b and x1
*March 24, 2015*

**math**

Ax + By + C = 0 so, the slope is -A/B take it from there...
*March 24, 2015*

**calculus**

as always, maximum area is when the fence is divided equally among lengths and widths. So, since I cannot see the diagram, but it implies the pens are in a row, we have six pens of length x and width y. 2x+7y = 540 area = 6xy = 6(540-7y)/2 * y = 1620y - 21y^2 This is a ...
*March 23, 2015*

**English**

Yes he is. My wife and I were granted permanent legal custody of him 3 years ago. He was abused and has been diagnosed with PTSD and a social disorder. I'm his learning coach since my wife still works and I check his homework.
*March 23, 2015*

**English**

thank you
*March 23, 2015*

**English**

One last question for the night. Then is it likely that thou wilt undertake/A thing like like death to chide away this shame. a- simile b- metaphor c- personification my answer is personification
*March 23, 2015*

**Geometry**

bingo
*March 23, 2015*

**Geometry**

ok. what did you get? (I know what I got) Did you try drawing a diagram?
*March 23, 2015*

**English**

Thank you all from a 68 year old Grandfather
*March 23, 2015*

**English**

Writeacher--that post this morning wasn't me. I did see your response though and it should be failure.
*March 23, 2015*

**English**

Complete the analogy, distraught is to affliction as sullen is to--- a- failure b- victory c-happiness I don't think any of them are right. I think it should be unhappiness so I'm stuck.
*March 23, 2015*

**English**

It wasn't one of the choices though. a- simile b- metaphor c- personification
*March 23, 2015*

**English**

Would it be personification then?
*March 23, 2015*

**English**

The tears have got small victory by that/ For it was, bad enough before their spite. I'm sorry I didn't list the last part.
*March 23, 2015*

**English**

poor soul they face is much abused with tears is what kind of figurative language my answer is metaphor
*March 23, 2015*

**Math**

5/9 x + 3/4 * 4/9 x + 7 = x x = 63
*March 23, 2015*

**Geometry 2**

The pentagon can be divided into 5 isosceles triangles, each with vertex angle 72 degrees. That should help you calculate the altitude (apothem). Then you're home free, right?
*March 23, 2015*

**Calculus**

the average slope is the slope of the line joining the two endpoints on the graph. Once you find that, the MVT says there is a c in the interval such that f'(c) = that slope. So, find that slope (call it m) and then just solve f'(c) = 10c+5 = m
*March 23, 2015*

**math**

if the squares have side s, then 6s = 60 and each square is 10x10. . . .
*March 23, 2015*

**Math**

1/3 R1 is [1 2/3 | 8/3] -5R1 + R2 is [-5 -10/3 | -40/3] +[5 2 | 12] = [0 -4/3 | 8/3] If things are garbled, fix 'em.
*March 23, 2015*

**Functions**

see the related questions below.
*March 23, 2015*

**Algebra**

(b^ 1/6)^3 = b^(1/6 * 3) = b^(1/2) b^(1/2) * b^(1/6) = b^(1/2 + 1/6) = b^(2/3) Do the others in like wise. Just do them step by step, multiplying or adding exponents.
*March 23, 2015*

**math**

well, the diagonal has length 8√2 the altitude of the triangular region is thus half that, or 4√2 So, the trapezoid has bases 8√2 and 4√2 and altitude 2√2 The area is thus 6√2 * 2√2 = 24
*March 23, 2015*

**pre algebra**

collect terms with the same powers: (2-6)x^2 + (-4+3)x + (8+7) -4x^2 - x + 15
*March 23, 2015*

**Math**

1.2x = 50.4
*March 23, 2015*

**geometry**

No idea what your garbled text means, but if the image is 10" tall, and must fit into a 6" frame, then it must be reduced by at least a factor of 6/10. Same for the width. So, since 8 * 6/10 = 4.8, the reduced picture needs to be 4.8 x 6
*March 23, 2015*

**math**

f(0) = 5 f(2) = 5 so, that is ok. f(x) is continuous since f is a polynomial, it is differentiable So, we want c such that f'(c) = 0 6c-6 = 0 c = 1 ok, since 1 is in [0,2].
*March 23, 2015*

**Math**

-2x^2y (-8x^3y^3 - 3x + 1 + 12y^3)
*March 23, 2015*

**English**

Distraught is to affliction as sullen is to a-failure b- victory c- happiness my answer is c
*March 23, 2015*

**math**

in this kind of stuff, always draw a triangle and label the sides. If you do that, you can easily see that cot x = 3/4 Or, use your basic trig identities sec^2 = 1+tan^2, so 1+tan^2 = 25/9 tan = 4/3 so, cot = 3/4 I assume you're working in QI, not QIV.
*March 23, 2015*

**maboa**

all useless, in my opinion.
*March 23, 2015*

**mathematical physics**

I'm sure you have this stuff already, http://en.wikipedia.org/wiki/Del_in_cylindrical_and_spherical_coordinates so why not just plug in your function?
*March 23, 2015*

**Physics**

(3.1/4.1)*240*(3.1/2) = (1/4.1)*240*(1.1/2) + 445x x = 0.56
*March 23, 2015*

**Calculus**

You know the growth function will look like g(t) = a*e^(kt) So, just plug in your numbers: g(0) = a = 45 g(8) = 45e^(8k) = 65, so k = ln(65/45)/8 = 0.046 Now just figure g(15)
*March 23, 2015*

**Algebra**

well, just plug it in and see what you get: y = 4(x+2) = 4x+8 so, y increases by 8. You could also have seen this by noting that the slope is 4, meaning that every time x increases by 1, y increases by 4.
*March 23, 2015*

**Math**

well, that would be 20.00 * 1.15
*March 23, 2015*

**Math**

a little of both comes in handy. Before deciding on a plan, do a little thinking. The clock gains 10 minutes every hour, so after h hours, it has gained 10h minutes. so, after 24 hours, the clock will be 240 minutes ahead. so, what time is 12:00 + 240 minutes?
*March 23, 2015*

**math**

it's the amount of surface showing.
*March 23, 2015*

**math**

I suspect that you have garbled the question somehow.
*March 22, 2015*

**math**

the equation has no angle. The line it describes has an angle θ such that tanθ = -3/2
*March 22, 2015*

**math**

well, when do you have -5t^2 + 20t + 15 = 3t + 3? once you have t, then plut it in to get h.
*March 22, 2015*

**Math**

that would be 630-210 = 420 It cannot be 630, since 210 of those also use Q.
*March 22, 2015*

**Physics**

all you have to do is conserve momentum before and after the collision m1*v1 + m2*v2 must be constant, so 60*17 + 26*26 = 60*v1 + 26*18.1 (a) 26*18.1 (c) solve for v1 above (b) 60*v1
*March 22, 2015*

**Chemistry, pre Algebra**

store pays .90 * 135/25 = 4.86 each assuming the $4 fee is per vial, the insurer pays (135+4)/25 * 1.03 = 9.56 each Not sure how the patient and insurer connect, but if the patient spent 22.50 for 5, and the insurer paid 5*9.56=47.80, then the store made 47.80 + 22.50 - 5*4.86...
*March 22, 2015*

**Physics**

as you said, the location of the center of mass does not change. So, since the boat weighs 4 times as much as the dog, it moves backward 1 foot for every 4 feet the dog moves forward. So, as you say, the boat has moved back 2 feet and the dog has moved forward 8 feet. That ...
*March 22, 2015*

**Math**

clearly it opens downward, since for equal increments of x, y is increasing, but more and more slowly. That means that soon it will turn around and start decreasing.
*March 22, 2015*

**Math**

first, there is no such word as miniscule. It is minuscule, and it is an adjective, not a noun. I have no idea which word you intended. you want to reduce the concentration by a factor of 10, so you need to increase the volume by a factor of 10. Since the original volume is ....
*March 22, 2015*

**Calculus Linearizations**

let y = √x that is, y^2 = x 2y dy = dx dy = dx/(2y) SO, given x = 16 y = 4 dx = -0.1, we have dy = -0.1/8 = -0.0125 That is, √(15.9) = y-dy = 4-0.0125 = 3.9875
*March 22, 2015*

**calc**

y = √x y^2 = x 2y dy = dx dy = dx/(2y) So, given x = 100 y = 10 dx = -0.4 dy = -0.4/20 = -0.02 so, √(99.6) ≈ 10-.02 = 9.98 actual value: 9.97998 As you can see, rather than using √(100-x) you just use √x and make a small adjustment. That way you ...
*March 22, 2015*

**Math**

The distance of (4,3) from (0,0) is 5. So, the circle is (x-4)^2 + (y-3)^2 = = 25 Now, you know that if the center were at (0,0), (±3,±4) and (±4,±3) would lie on the circle. So, shift those possibilities right and up, and see what drops out. (7-4)^...
*March 22, 2015*

**Maths**

well, you need to find the midpoint. That is at the average of the ends: (-1,0). Now just find the distance from there to (0,0). If the radii are a,b,c we have b = 5/4 a c = 4/5 b = 4/5 * 5/4 a = a so, the radii are the same, and hence the areas as well. Note that we don't...
*March 22, 2015*

**Pre ALGEBRA**

No idea, but it sure sounds like a dumb-ass way to model algebraic expressions. I can't decide just what means what You have black square white thin black thin white small square black small Clearly the question is garbled, or some geometric grouping is to suggest ...
*March 22, 2015*

**algebra. . please help**

rationalizing denominators depends on the fact that (a+b)(a-b) = a^2-b^2 So, if you multiply top and bottom by (3-√5), you have 4(3-√5) -------------- (3+√5)(3-√5) 4(3-√5)/(9-5) = 3-√5
*March 22, 2015*

**Math**

#1. I can't see where any n comes in at all. The chance of guessing the 3 digits in order is 1/5 * 1/4 * 1/3 That is, since there are 5P3=60 ways of picking 3 digits, and only one is correct, that's 1/60 chance of getting it right. #2 avg speed = totaldistance/...
*March 22, 2015*

**Algebra 1**

thank you
*March 22, 2015*

**Algebra 1**

what method would you use to solve y=x?
*March 22, 2015*

**math**

that works if she's now at 65.
*March 22, 2015*