Thursday

September 29, 2016
Total # Posts: 44,224

**Math**

differences: -1/3, 1, -3 ratios: 0, ∞, -2 since neither is constant, it is neither an A.P. or a G.P. So, how to figure the next terms? Note that the differences form a G.P., with the next terms 9,-27,81 Adding those to -2, we get 7,-20,61, or choice (A)

*August 27, 2016*

**Maths**

If you take the time to list the possible events qnd the contents of the jqr qfter eqch, the qnswer will become cleqr. qnnoying, isn't it?

*August 27, 2016*

**Maths**

2/3 * 2/3

*August 27, 2016*

**real analysis**

google is your friend http://math.stackexchange.com/questions/283987/interior-closure-and-boundary-of-the-sets-of-all-rational-and-irrational-number

*August 27, 2016*

**Higher Math**

tan10x = 2tan5x/(1-tan^2(5x)) so, 2tan(5x)/(1-tan^2(5x)) = 1/tan(5x) 2tan^2(5x) = 1-tan^2(5x) 3tan^2(5x) = 1 tan 5x = ±1/√3 Now use that to get your reference angles and produce as many solutions as your domain requires.

*August 27, 2016*

**Math**

height: h width: h+4 length: w+8 = h+12 h(h+4)(h+12) = 512 all the factors of 512 are powers of 2, so we have 2^9 = 512 2+3+4 = 9 2^2 * 2^3 * 2^4 = 512 4*8*16 = 512

*August 27, 2016*

**math**

when n=1, A1 = -7*1+8 = -7+8 = 1 now just start subtracting 7 again and again.

*August 27, 2016*

**math**

since you keep multiplying by -1, there will be (n-1) of them by the nth term.

*August 27, 2016*

**math**

Check the ratio between terms. If it constant, choose it. For example, -6/2 = ?

*August 27, 2016*

**math**

F is the first term None of the choices identifies the first four terms

*August 27, 2016*

**maths**

9999999 - x = 6543210

*August 27, 2016*

**Math**

heads: s+a=10 legs: 8s+6a=68 Now just solve for s and a.

*August 27, 2016*

**math just for fun**

111*16 = 1776 pages Looks like 4 reams will do the job. So, how much will that cost? If only paying for the paper used, that would end up as 1776/500 * 3.88

*August 27, 2016*

**math**

.70p = 35

*August 27, 2016*

**Math**

Also, note that you have not said which numeric grade is equivalent to a B. Nor have you said how many items remain to be graded. If you can't specify the requirements, how can you expect a solution?

*August 26, 2016*

**Math**

512 = 8^3 = 2^9

*August 26, 2016*

**math**

it has an inverse, since f^-1(x) = ∛(x-8) + 2 Also, you know that g(x) = x^3 is 1-to-1, and f(x) is just g(x) shifted by (2,8). More formally f(x) is one-to-one if f(a) = f(b) means that a = b so, let's say that f(a) = f(b) That means that f(a) = f(b) (a-2)^3+8 = (b-...

*August 26, 2016*

**Physics**

you forgot the depth: 1cm Though it makes the units come out, it does not affect the final numerical value. Looks good.

*August 26, 2016*

**12th grade physics**

1000 cosθ where sinθ = 15/40

*August 26, 2016*

**algebra**

what do you mean by reasonable? Is 23.62 less reasonable than 23 ?

*August 26, 2016*

**maths**

minimum cost is at the vertex of the parabola. As usual, that occurs at x = -b/2a = 10/0.5

*August 26, 2016*

**geometry**

clearly AB has been rotated 1/4 turn to the left. Since the triangle is still the same size (AB has the same length as A'B'), we just need to find the translation. (-3,4) --> (-2,-3) so it has been moved by (1,-7) Now just convert those two changes to your standard ...

*August 26, 2016*

**geometry**

With no figures to consult, it's very hard to say ...

*August 26, 2016*

**Math**

seven digit number xxxxxxx digit 3 in my ten thousands and tens places xx3xx3x carry on from here

*August 26, 2016*

**calculus**

see whether you can come up with the answer shown at http://www.wolframalpha.com/input/?i=inverse+%7B%7B16,1%7D,%7B1,16%7D%7D

*August 26, 2016*

**calculus**

Review the definition of matrix multiplication. See if you can come up with the answer shown at http://www.wolframalpha.com/input/?i=%7B%7B3,8%7D,%7B6,3%7D%7D*%7B%7B4,5%7D,%7B4,4%7D%7D

*August 26, 2016*

**algbra**

I believe √100 = 10, not 5 anything that is only concerned with integers and fractions is rational. √19 is irrational nope pi is irrational the √ values are irrational only (a) is rational I think you have some reviewing to do...

*August 26, 2016*

**calculus**

eh? just subtract corresponding elements: [1 5 2] ...

*August 26, 2016*

**Math**

1.08x <= 18

*August 26, 2016*

**algebra 1**

both correct. Although, I don't think Best Buy sells cereal...

*August 26, 2016*

**Maths**

As always, draw a diagram and review your basic trig functions. If B is at height h above A, then h/600 = sin11° Now, if the distance CA is x, x = 600cos11° + h cot23°

*August 26, 2016*

**maths**

since 3/4 of each, that means 3/4 of their total. (3/4)t + (3/4)c = (3/4)(t+c)

*August 26, 2016*

**Math**

recall that for odd powers, a^n + b^n = (a+b)(a^(n-1) - a^(n-2)*b + ...) since 4+6=10, the product is a multiple of 10, so dividing by 5 leaves a remainder of zero. (D)

*August 26, 2016*

**physics**

solve 35t - 4.9t^2 = 0

*August 26, 2016*

**Lost**

3000c - 900 = 3750 3000c = 4650 c = 4650/3000 or, more directly c = (p+e)/n

*August 26, 2016*

**Math**

if n is any value except zero, n/n = 1

*August 26, 2016*

**Math**

list the pairs of factors of 60 and 75 The more factors, the more ways they can be arranged.

*August 26, 2016*

**Analogy**

eighteen:even::thirty-three:odd

*August 26, 2016*

**Chemistry**

convert to moles, then multiply by Avogadro's Number

*August 25, 2016*

**Math**

see related questions below

*August 25, 2016*

**Physics I - Modern**

it's mv/√(1 - v^2/c^2) see http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/relmom.html

*August 25, 2016*

**Math**

well, a 150lb person on the moon would weigh (150/120) * 20 = 25lb

*August 25, 2016*

**Math**

no idea. try google

*August 25, 2016*

**physics**

40 mi/hr * 1609m/mi * 1hr/3600s * 60s/min * 3min = 1073.7 m

*August 25, 2016*

**7th grade math**

clearly, two of the three possible discounts will give enough discount so that the final price with tax will be less than $25. So, probability is 2/3

*August 25, 2016*

**7th grade math**

There are 8 possible outfits with the shoes and bottoms. So, what is the smallest multiple of 8 that is at least 35? Using n tops, he gets 8n outfits.

*August 25, 2016*

**Pre-calculus**

Since the axis is horizontal, the general equation is x = a(y-k)^2 + h Since the vertex is at y=k, k = h and that means x = a(y-k)^2 + k Using the two points, we have a(-2-k)^2 + k = 6 a(4-k)^2 + k = 3 solve those, and you wind up with x = 1/4 (y-2)^2 + 2 x = 5/36 (y-14/5) + ...

*August 25, 2016*

**math**

1/4 + 5/8 + x + 3/4 = 2 1/2 Now just solve for x did you get 7/8 ?

*August 25, 2016*

**Math**

since distance = speed * time, if your speed is x, then 2*x + 2*2x = 258

*August 25, 2016*

**physics**

The ball's height is modeled by h(t) = 15t - 4.9t^2 The ball will be 8m high twice: on the way up and on the way down. These times can be found by solving 15t - 4.9t^2 = 8 See http://www.wolframalpha.com/input/?i=15t+-+4.9t%5E2+%3D+8 If you include the units in your ...

*August 25, 2016*

**MATH**

(36-30)/30 * 100

*August 25, 2016*

**Maths**

there are 48*16 food portions after 4 days, 48*4 portions have been eaten. So, there is enough for (48*16 - 48*4)/(48-12) = 16 days or, after 4 days, 1/4 of the food is eaten. That leaves enough for 12 days for the full population. But, the population is now 3/4 what it was, ...

*August 25, 2016*

**value**

m/d = 8/5 d = 15, so m=24 so, what is m-6?

*August 25, 2016*

**Maths**

start with cot(x/2) = sinx/(1+cosx) and see where you can take that.

*August 25, 2016*

**maths**

just list the factors of 72, and work with that, depending on how many piles you want: 1 72 2 36 2 2 18 2 2 2 9 ... 3 3 8 3 24 and so on

*August 25, 2016*

**alg. Connections**

total points for an 85 average: 85*3 = 255 Points so far: 81+86 = 167 So, haw many does she still need?

*August 25, 2016*

**algebra HELP MRS SUE**

B is better :-)

*August 25, 2016*

**lauren**

If $x at 11%, then the rest $(6300-x) is at 7%. So, just add up the interest: .11x + .07(6300-x) = 565

*August 25, 2016*

**value**

And surely the ratio is 4:3, not 40:3 maybe for bread 40:3 would be appropriate, as it is not so sweet as a cake.

*August 25, 2016*

**Geometry**

You may be right, but I have no diagram, so it's hard to say; but they do add up to 180°, so they are also supplementary.

*August 25, 2016*

**maths**

visit https://www.learnnext.com/nganswers/ask-question/answer/OPQR-is-a-rhombus-three-of-its-vertices-lie-on-the-circle-/Areas-Related-to-Circles/18625.htm

*August 25, 2016*

**Science**

1.5 m/hr * 1hr/3600s = 1/2400 m/s now, recall that time = distance/speed and use that what are you, a slug? Maybe you meant 1.5 km/hr. If so, jack up the speed by a factor of 1000.

*August 25, 2016*

**math**

well, just add the fractions: 1/4 + 1/3 + 1/2 + 7/12 + 3/4 + 5/6 + 1 = 3/12 + 4/12 + 6/12 + 7/12 + 9/12 + 10/12 + 12/12 = (3+4+6+7+9+10+12)/12 = 51/12

*August 24, 2016*

**Math**

assuming straight-line depreciation, then it will have lost (10/4)(.25) = .625 = 5/8 of its value So, it will be worth 3/8 of 21000 or $7875

*August 24, 2016*

**Math - Composition of Functions**

huh? really? g(x) = 1/x so, f(x) = g◦h = 1/h = 1/(x+1)

*August 24, 2016*

**math**

1xxx1 or 1xxx7 now just fill in the other 3 digits in the 6 ways possible

*August 24, 2016*

**math**

Hmmm. I see it as $54(1/6) + (1/2)($18(1/6)) = $12

*August 24, 2016*

**Math**

x y

*August 24, 2016*

**Math**

why are you guessing? I hope you actually did some kind of calculation. since cos(kx) has period 2pi/k, cos(pi/3 x) has period 6 the rate of change is y' = -pi/3 sin(pi/3 x) so, it is zero at pi/3 x = 0 or pi or 2pi; that is, x = 0,3,6 sin(pi/3 x) is at a max when pi/3 x...

*August 24, 2016*

**physics vectors**

the final vector will have x- and y-components. The direction θ is such that tanθ = y/x

*August 24, 2016*

**physics vectors**

so, get out your graph paper, plot the vectors and measure the final vector.

*August 24, 2016*

**Math**

12(3+2)

*August 24, 2016*

**math**

if the three numbers are x-1, x, x+1 then you know that x+1 = (x-1)/2 + 2 or x+1 = (x-1+2)/2 depending on how you parse the words

*August 24, 2016*

**MATH - again?**

Damon already did this one for you.

*August 24, 2016*

**calculus**

x^2+4y^2+16z^2−64 = 0 16z^2 = 64-x^2-4y^2 2z ∂z/∂x = -2x 2z ∂z/dy = -8y so, ∂z/∂x = -x/z ∂z/∂y = -4y/z ∂^2z/∂x^2 = -(x^2+z^2)/z^3 and you can do the others similarly, using the quotient rule or the product rule

*August 24, 2016*

**math**

subtracting a smaller number results in a greater difference.

*August 24, 2016*

**Economics**

Assuming that all the variable cost is labor, that would make wages for (50-30)/2 = 15 units

*August 24, 2016*

**Math**

note that this is also just (x+y)/2 + (7+17)/2

*August 24, 2016*

**Math**

(x+y)/2 = 10 (x+7 + y+17)/2 = (x+y + 24)/2 = (x+y)/2 + 24/2 = 10+12 = 22

*August 24, 2016*

**Physics**

lnx x^y + lny y^x - ----------------------------------- x^(y-1) + y^(x-1)

*August 24, 2016*

**business**

total_grade=0fori=1to4readscore[i]totalgrade+=score[i]nextiaverage=total_score/4fori=1to4displayi,": ",score[i]nextidisplay"average: ",average

*August 24, 2016*

**math**

area is circumference times height, so 14πd = 396 assuming open ends.

*August 24, 2016*

**math**

not quite sure which direction 60°north and 45°east is supposed to be.

*August 24, 2016*

**math**

no idea what x is, but each leg is 145/√2

*August 24, 2016*

**maths**

120-(60+50-20)

*August 24, 2016*

**math**

see http://www.askiitians.com/forums/Trigonometry/prove-cot-a-cot-60-a-cot-60-a-3-cot3a_106221.htm for one solution. You might try proving it without recourse to sin and cos.

*August 24, 2016*

**Kaplan**

their combined speed is 67 mi/hr so, which two numbers differ by 9 and sum to 67? x-y=9 x+y=67 ...

*August 24, 2016*

**Math**

if you use your sum-to-product formulas, you will see that the results is a real number. imaginary part is zero

*August 23, 2016*

**Math**

you have a 7-24-25 triangle, in QII cosθ = x/r = -24/25

*August 23, 2016*

**physics vectors**

A+B = 2i-7j tanθ = -7/2 in QIV A-B = 4i+5j tanθ = 5/4 in QI

*August 23, 2016*

**science**

treating the vectors as complex numbers, we have 75i + 250 + 109cis(pi/6) - 156i = 344.4 - 26.5i or, in polar form, 345.4 @ E4.4°S

*August 23, 2016*

**math help me out**

does that mean p received 80% of the profit?

*August 23, 2016*

**Maths**

assuming simple interest, you want P*.25/2*4 = 8560*0.12*5 not quite sure what 25/2% means, but if I got it wrong, just fix it.

*August 23, 2016*

**Algebra 1**

not whole numbers rational integer

*August 23, 2016*

**Math**

1 ml, 20 ml, 979 ml Pick any three distinct numbers that add up to 1000

*August 23, 2016*

**Math**

just as you cannot subtract 7 from 2 in 32 - 17 you change 32 to 20+12 Now you can borrow the 7 from 12, leaving 15 2 hrs 2 minutes is the same as 1 hr 80 minutes. Now you can subtract from a number bigger than 20.

*August 23, 2016*

**math**

assuming you can draw tallies, just make the marks, usually in groups of 4 lines with a crossing line for 5. See https://www.google.com/search?q=tally+marks&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiljfC-xdjOAhVK6WMKHdHWDDoQsAQITA&biw=1541&bih=852

*August 23, 2016*

**Algebra**

flip each side and you have 1/x + 1/y = 1/6 6/x + 6/y = 1 6x+6y = xy Not sure just where you want to go with this. Clearly, 1/2 + -1/3 = 1/6

*August 23, 2016*

**math data management**

she needs at least 4 out of the remaining 8 questions correct. So, that has probability This topic is discussed here: http://math.stackexchange.com/questions/853407/4-heads-in-8-tosses

*August 23, 2016*