Sunday

September 25, 2016
Total # Posts: 44,023

**Algebra**

since distance = time * speed, 7(x-y) = 28 4(x+y) = 48

*September 13, 2016*

**Algebra**

well, 7-4 = 3

*September 13, 2016*

**Algebra**

(1/5)x - (1/9)(x+1) = 3

*September 13, 2016*

**differential calculus**

how about v = 120000 * 0.92^t ??

*September 13, 2016*

**Maths**

If this much time has passed with no response, it is usually an indication that no one is sufficiently versed in statistics and probability theory that they feel they can provide useful help. I know that I'd have to review my textbooks to work it out. Believe it or not, we...

*September 13, 2016*

**Physics**

You have 5v + a/2 * 5^2 = 40 10v + a/2 * 10^2 = 105 Now just solve for v.

*September 13, 2016*

**Triangles**

yes

*September 13, 2016*

**Triangles**

13-10 < x < 13+10

*September 13, 2016*

**mathematical phyaics**

using the determinant form, two rows are the same, so the determinant is zero

*September 13, 2016*

**mathematical phyaics**

You have probably already seen that Ax(wxu) = w(A.u)-u(A.w) Now let A = vxw Then (vxw)x(wxu) = w(uxvxw) So, (uxv).(vxw)x(wxu) = (uxv).w(u.vxw) = (uxv.w)(u.vxw) = (u.vxw)^2 There are other proofs online

*September 13, 2016*

**mathematical physics**

a' = i + e^t(t^2+2t)j + 2cos2t k T = a'/|a'|

*September 13, 2016*

**Math**

just solve -16t^2 + 64t + 4 = 6464

*September 13, 2016*

**math**

24 = 2^2 * 3 48 = 2^3 * 3 52 = 2^2 * 13 so, what is the LCM?

*September 13, 2016*

**science,physics**

if moving in opposite directions, 3*5 = 2v

*September 13, 2016*

**MATHS2**

https://answers.yahoo.com/question/index?qid=20061106084200AAifTZM

*September 13, 2016*

**math 101**

.06x + .15*2 = .12(x+2)

*September 13, 2016*

**Math 172**

it's when R(x) = C(x) 23x = 14x+9000 Now just solve for x, then evaluate y.

*September 12, 2016*

**Math**

won't work. You must have balanced parentheses. Hint: 9*2 = 18

*September 12, 2016*

**math**

depends on how many were in the big bag, which you did not say.

*September 12, 2016*

**Math**

(u-5v)x(u+4v) = uxu - 5vxu + 4uxv - 20vxv = 9uxv (why?)

*September 12, 2016*

**math**

time = distance/speed, so t = 50/s

*September 12, 2016*

**Math**

one is a power of 2, one is an odd multiple of 2.

*September 12, 2016*

**Algebra 2**

b = bh/2 - 3 h = bh/2 - 6 bh/2 = b+3 = h+6 so, h = b-3 b = b/2 (b-3) - 3 2b = b^2-3b-6 b^2-5b-6 = 0 b = 6 or -1 pick b=6 so, h=3 bh/2 = 6*3/2 = 9

*September 12, 2016*

**math**

I think you mean difference of squares (3a-4)(3a+4)

*September 12, 2016*

**Calculus**

a = 2i + 6tj + 12t^2k v = 2ti + 3t^2j + 4t^3k + c at t=0, v=i, so c = i and v = (2t+1)i + 3t^2j + 4t^3k r = (t^2+t)i + t^3j + t^4k + c use r(0) to see that c = 2j-7k so r = (t^2+t)i + (t^3+2)j + (t^4-7)k

*September 12, 2016*

**Math**

-8 and -8

*September 12, 2016*

**math**

that already is

*September 12, 2016*

**Calculus**

just use the definitions in your text. Simple derivatives.

*September 12, 2016*

**matematicas**

xxx si, pero no es un ano (hablo portugues)

*September 12, 2016*

**matematicas**

si, mas no es un ano

*September 12, 2016*

**matematicas**

x = ano de mi nacimiento este ano = 1997 x+1997 - (x+10) - (x+15) + (1997-x) = 80 Hmmm. Debo de haber cometido un error. Pero se entiende la idea: poner las palabras en matemáticas

*September 12, 2016*

**math**

9i - 5 - 3i -5 + 6i

*September 12, 2016*

**math**

hint: the i stands for imaginary

*September 12, 2016*

**MATH**

(634/10) * 14 inches

*September 12, 2016*

**math**

numerical expressions

*September 12, 2016*

**Maths**

dilation

*September 12, 2016*

**Solid mensuration**

since the top diameter is 7/12 as big as the bottom diameter, the missing piece has a slant height of (7/5)(13) So to figure the numbers for the frustrum, find them for the entire cone and subtract the value for the missing piece. Or, since the frustrum is 7/19 as high as the ...

*September 12, 2016*

**Math**

the probability of getting any six specific tosses is (1/2)^6

*September 12, 2016*

**algebra**

so, just plug in your numbers!

*September 12, 2016*

**Algebra**

spot on.

*September 12, 2016*

**Calculus**

the density will be the (average value of the population) divided by the area just as we had to integrate the density times area to get total population . Remember that the average value of f(x) in the interval [a,b] is ∫[a,b] f(x) dx ------------------ ...

*September 12, 2016*

**Calculus**

funny how much time google can save you http://www.math.ucla.edu/~ronmiech/Calculus_Problems/32A/chap11/section7/732d51/732_51.html

*September 12, 2016*

**Calculus**

see your text for examples, or http://mathinsight.org/parametrized_curve_tangent_line_examples

*September 12, 2016*

**Math**

#1. Just pick any 6 consecutive integers and try it out #2. Consider the numbers x-2, x-1, x, x+1, x+2 #3. Should be clear. Even if you're not sure about some of them, the right one jumps out. #4. any multiple of 2 is even #5. start by noting that 17 is prime #6. trick ...

*September 12, 2016*

**algebra**

solve for what? And of course, it's probably vt, not ut.

*September 12, 2016*

**algebra**

do the division. If the remainder is subtracted, the new remainder will be zero.

*September 12, 2016*

**SS ICY NORTH**

I see someone else (not you?) was asking about Canada icy north google turned up several references for that

*September 12, 2016*

**SS ICY NORTH**

Hmmm. I see a few hits on google, but they relate to different topics. I see your subject is social studies. What kind of ICY NORTH are you referring to? Climate, Rock Band, what?

*September 12, 2016*

**SS ICY NORTH**

google

*September 12, 2016*

**Physics**

46 mi/hr = 20.56 m/s so v = at means t = 20.56/2.35 s work the other similarly or, just consider the ratio of time lengths

*September 12, 2016*

**profit and loss**

do you mean that If he now gets x eggs for rs10 he would get x+6 eggs or the discount lets him get 6 eggs for rs10?

*September 12, 2016*

**Science**

try this https://www.google.com/#q=inductive+vs+deductive is that your final answer?

*September 12, 2016*

**Calculus**

The population in a ring of radius r is density * area, so adding up all the rings you get ∫[0,7] 6∛(3+r^2) * 2πr dr hint: let u = 3+r^2 for the volume, you can use shells: ∫[0,5] 2πrh dx = ∫[0,5] 2πx(5x-x^2) dx discs: ∫[0,25] π...

*September 12, 2016*

**physics**

https://www.google.com/#q=drift+velocity+area+conductor

*September 12, 2016*

**Algebra2**

well, assuming your = means +, 6x+9y=6 6x-10y=44 ...

*September 12, 2016*

**Math**

f(x) = (1/x)^(sinx) = 1/(x^sinx) Let us take the limit as x→0+, since rasning negative numbers to real powers is not well defined. consider limit x→0 g(x)=x^x lng = x lnx = lnx/(1/x) limit ln g(x) as x→0 = (1/x)/(-1/x^2) = -x limit ln(g(x)) = 0 so, limit g(x...

*September 12, 2016*

**Maths Percentage**

1.4 * ate = 70 ate = 50 what do you get for the other parts? If you get stuck, show how far you got. You must have at least some idea where to start, even if it is only defining a variable.

*September 12, 2016*

**precalculus**

ok. It appears to be in QIV, and is a 12-35-37 right triangle. If you draw it correctly, you should be able just to read off the values of the trig functions of that angle.

*September 12, 2016*

**Maths Percentage**

Syed's is 5/4 of Emraan's So, Emraan's is 4/5 of Syed's

*September 12, 2016*

**Math**

no problem. Feel free to stop by any time, but next time you need to ante up some work before we bother betting.

*September 12, 2016*

**Math**

As written, I get none of the above. Show your work, and we can check what's going on. To get -16, the 2nd term must come out to -32, since 16-32 = -16

*September 12, 2016*

**mechanic**

200^2 + 200^2 - 2*200*200cos(π-θ) = 100 the two forces must be very nearly in opposite directions.

*September 12, 2016*

**science**

120g/6mL = 20g/mL

*September 12, 2016*

**Math**

.10*100 + .20*89 + .55*82 + .15*81 ≈ 85

*September 12, 2016*

**Calculus**

well, I get -114.755 so maybe the key wants -114.76 or -114.8 or -115

*September 12, 2016*

**Calculus**

I think you subtracted wrong. Try (f(4)-f(-5))/9 = -114.75 as a quick look at the graph would indicate: http://www.wolframalpha.com/input/?i=3x%5E3-12x%5E2

*September 12, 2016*

**Calculus**

L'Hospital's Rule: (1/(1+x^2) - 1)/(3x^2) = (-x^2/(1+x^2))/(3x^2) = -1/(3(1+x^2)) -> -1/3

*September 12, 2016*

**Math**

if there are 5x girls and 12x boys, then 17x = 5200 Hmmm. 17 does not divide 5200. Now, if there were 5100 students, then x = 300.

*September 12, 2016*

**Maths**

well, 25tanx = 17cosy, so see what you can do with that.

*September 12, 2016*

**Math**

what, no ideas of your own? at all? none?

*September 12, 2016*

**Math**

1: 5.310 5: 101.1 now you try the others. we'll check your results

*September 12, 2016*

**Math**

c = πd love your creative syntax

*September 12, 2016*

**maths**

ok, now what?

*September 12, 2016*

**Math**

a = (17-8)/3 = 3 m/s^2 s = vt + a/2 t^2

*September 12, 2016*

**Math**

Well, just plug in n=101! (101+1)x+(-1+2(101-1)) = 102x + 199

*September 12, 2016*

**math**

(n+1)x + (-1 + 2(n-1))

*September 12, 2016*

**Math**

no clue. no info.

*September 12, 2016*

**algebra**

yes

*September 11, 2016*

**a**

No idea where the u and z came from, but the -8x-3y is ok

*September 11, 2016*

**maths**

here's a nice linear algebra solver: http://www.zweigmedia.com/RealWorld/LPGrapher/lpg.html

*September 11, 2016*

**Math**

use the law of cosines. The included angle is 50°

*September 11, 2016*

**physic**

at time t they will be at the same height, when 17-4.9t^2 = 23.5-7.36t-4.9t^2 use that t to get the height since gravity affects both balls equally, their speed difference is constant.

*September 11, 2016*

**4th grade math**

21,849 + 38,932 ≈ 20,000+40,000

*September 11, 2016*

**Math**

90-105 = ?

*September 11, 2016*

**Precalculus**

xy = 172 x = 2y-8 solve for x and y, and then the diagonal is √(x^2+y^2)

*September 11, 2016*

**Math**

5 1/6 = 30/6 + 1/6 = ?

*September 11, 2016*

**ALGEBRA**

If there are x ml of 20% then the rest (100-x) is 40%. So, add up the acid in the parts; it must equal the acid in the result: .20x + .40(100-x) = .24*100 and that's liters, not leters. When you get your answer, note that 24% is 1/5 of the way from 20 to 40, so 1/5 of the ...

*September 11, 2016*

**Math**

y-x = 20 (x+y)/3 = 40

*September 11, 2016*

**college**

60 rev/min * 2π rad/rev = 120π rad/min the linear speed is just radius * angular speed 120π/min * 15in * 1ft/12in * 1min/60s = (120π*15)/(12*60) ft/s

*September 11, 2016*

**math**

First step: distributive 6x-8 = 8x-11 now what?

*September 11, 2016*

**Math**

Tn must surely be (n+1)x + (-1 + 2(n-1)) = (n+1)x + 2n-3

*September 11, 2016*

**math**

note that S increases by 5 for every +1 change in N.

*September 11, 2016*

**Math**

exactly reversed. How can you possibly add two positive numbers and sometimes get a negative result???

*September 11, 2016*

**Algebra**

y = mx+b 21m+b = 58 43m+b = 42.6 Solve for m and b, and then figure y when x=59. Or, note that 22 minutes of driving covered 15.4 miles. So, after 16 more minutes, he covers (16/22)(15.4) more miles. Subtract that from 42.6

*September 11, 2016*

**Algebra 1 Foundation Concepts rewrite**

6 B,C http://www.virtualnerd.com/algebra-2/equations-inequalities/real-numbers/number-types/natural-and-whole-numbers-definition Surely your text explains all this.

*September 11, 2016*

**Math**

(a) 10(+0.30) = +3.00 That's my work so far. Have any of your own?

*September 11, 2016*

**Math Trigonometry**

use the law of cosines. The included angle is 50°

*September 11, 2016*

**Mathematics**

(b) clearly d=4, since T16-T8 = 8d = 32 Now do (a) and (c) For (c), note that T20-T16 = 4d

*September 11, 2016*

**Math Trigonometry**

actually, if you draw the parallelogram, you will see that you have the wrong diagonal. R^2=22^2+35^2-2*22*35*cos(180-52) If the vectors are u and v, you want |u+v|, not |u-v|

*September 11, 2016*