Friday

December 2, 2016
Total # Posts: 46,753

**mathematics**

what? reposting after just 5 minutes?

*November 21, 2016*

**maths**

well, 6 = 72/12, so ...

*November 21, 2016*

**Mathematics**

Let the ages of France, Emma, Father be x,y,z. Then we have x = 2y x+y = z-12 z=30 So, start substituting till you can find y.

*November 21, 2016*

**Algebar**

you have a difference of two squares a^2-b^2 = (a-b)(a+b) where a = 9x^3 b = 5y^5 Now just plug and chug.

*November 21, 2016*

**math**

chain rule: (a) 4(x^2+1)^3 * 2x (b) not sure what you mean by "primitive" The extrema (max and min) can be found where 8x(x^2+1)^3 = 0

*November 21, 2016*

**maths**

22.5

*November 21, 2016*

**Math**

x-21 = 71-x

*November 21, 2016*

**motion**

Take a look at this example. It is very similar to yours. http://www.a-levelmathstutor.com/m-momimp-coeffrest.php

*November 21, 2016*

**Math, Surds @Reiny got it**

My bad. I read "diagonal" not "area"

*November 21, 2016*

**Math, Surds**

s = 60/?2 = 30?2 m well, a square has 4 sides, so ...

*November 21, 2016*

**math**

m-1/m ... what? I will say, however, that (m-1)^2/m^2 = ((m-1)/m)^2 (m^2-1)/m^2 = (m-1)(m+1)/m = (m-1)/m * (m+1)

*November 21, 2016*

**Chemistry**

Looks like 205g to me.

*November 21, 2016*

**Maths**

My bad. I should have said that when ?=1 we get the equation x^2 + y^2 +4x - 3 + 1(2x^2 + 2y^2 +4x -6y + 3) = 0 3x^2+8x + 3y^2-6y = 0 (x + 4/3)^2 + (y-1)^2 = 25/9 Now the three circles can all be seen to intersect at the same two points: http://www.wolframalpha.com/input/?i=...

*November 21, 2016*

**Maths**

When ?=1, we get the circle (x+2)^2 + (y-1)^2 = 5 The three circles can be seen at http://www.wolframalpha.com/input/?i=plot+x%5E2+%2B+y%5E2+%2B4x+-+3+%3D+0,+++2x%5E2+%2B+2y%5E2+%2B4x+-6y+%2B+3+%3D0,+(x%2B2)%5E2+%2B+(y-1)%5E2+%3D+5,+y%3D0,+x%3D0

*November 21, 2016*

**Maths**

Solving the system of equations x^2 + y^2 +4x - 3 = 0 2x^2 + 2y^2 +4x -6y + 3 =0 Is the same as solving the system x^2 + y^2 +4x - 3 = 0 ?(2x^2 + 2y^2 +4x -6y + 3) = 0 The equation x^2 + y^2 +4x - 3 + ?(2x^2 + 2y^2 +4x -6y + 3) = 0 can be written as (*) (1+2?)x^2 + 4(1+2?)x...

*November 21, 2016*

**math-mechanics 1**

(a) v = 2i (b) r = 2it + (-0.2i+.05j)t^2 (c) we want r to have a zero i component. So, 2t - 0.2t^2 = 0 0.2t (10-t) = 0 t=10 (d) v = 2i + (-.4i+.1j)t we want the i and j components to be equal, so 2-.4t = .1t 2 = .5t t = 4

*November 21, 2016*

**Math**

If the tree's height is x meters, the broken tree forms a right triangle with sides 12/25 x and 10. The hypotenuse is 13/25 x. 10^2 + (.48x)^2 = (.52x)^2 Now just solve for x.

*November 21, 2016*

**Math**

well, how many months in 4 years? 423 each month...

*November 21, 2016*

**algebra 1**

x = 7y/4 + 3/4 y = 4x/7 + 3/7 x = -3y/4 - 7/4 y = -4x/3 - 7/3

*November 20, 2016*

**MATH**

:DDDDDDDDDDDDDDD

*November 20, 2016*

**MATH**

So to restate it in this account that I have been asking the questions and was granted your help. Oh wow that is interesting Ms. Sue and I want to do that with my life also, but sometimes I need some light on how to do these problems. The question I got wrong was a question I ...

*November 20, 2016*

**MATH**

Sorry Ms. Sue I had logged on to my account and answered your post on that account but it was really me STEVE as Your best friend

*November 20, 2016*

**MATH**

THANKS MS. SUE I got 21/22 questions correct I HATE THAT I WANT 22/22 my mom will get really mad so I have to correct the problem I got wrong before she finds out but thank you for the help for the rest of the questions

*November 20, 2016*

**MATH**

3. (5 * 2.25) - (5 * 0.65) = 8 or $8.00 4. Thank you

*November 20, 2016*

**MATH**

1.= 3.2*10^6 NOW I JUST NEED HELP WITH QUESTIONS 3 AND 4 Thank you Ms. Sue for all of your help so far

*November 20, 2016*

**MATH**

3. THAT EQUATION DOES NOT WORK Ms. Sue IT EQUALS $9.95 AND 9.95 IS NOT AN ANSWER

*November 20, 2016*

**MATH**

1. WOW YOU DON'T KNOW, WELL I DON'T KNOW EITHER 2. (2/3) * (1/4) = 1/6 3. (5 * 2.25) - (2 * 0.65) = 9.95 4. A OR B

*November 20, 2016*

**MATH**

These are my last few question that I need help with PLEASE STAY WITH ME MS. SUE 1. In 2012, the total population of Florida was 3,158,697 people. What was the population in scientific notation, approximately? A. 3.2 * 10^5 B. 3.2 * 10^6 C. 3.2 * 10^7 D. 32 * 10^7 2. If there ...

*November 20, 2016*

**math**

rate of change is (y-change)/(x-change) For the table shown, check each section. The rates from point to point are (70-30)/(15-0) = 2 (0-70)/(23-15) = -70/8 (45-0)/(30-23) = 45/7 (60-45)/(35-30) = 3 absolute values are always positive. So, just compare the positive values ...

*November 20, 2016*

**MATH**

No she would so estimated it would be just 2 or B Sorry for the confusion Ms. Sue Thank you

*November 20, 2016*

**MATH**

3 * (7/8) = 2 5/8 yards (7/2) / (14/9) = 2 1/4 pieces Thank you Ms. Sue but I don't get you 2nd equation It equals 2 1/4 but that is not an answer choice

*November 20, 2016*

**MATH**

1. Serena has 7/8 yd of fabric. To complete her craft project, she needs 3 times that amount. How many yards of fabric does Serena need? A. 2 5/8 B. 2 7/8 C. 3 3/7 D. 3 7/8 2. A length of ribbon is 3 1/2 yd long. How many pieaces 1 5/9 yd long can Joy cut from the length of ...

*November 20, 2016*

**Math**

Thanks anyways.

*November 20, 2016*

**Math**

So it would Be C

*November 20, 2016*

**Math**

Thanks Ms. Sue and Reiny A. 1/3 B. 1/4 C. 1/2 D. 1/8

*November 20, 2016*

**Math**

Or 1/2

*November 20, 2016*

**Math**

it = 0.5

*November 20, 2016*

**Math **

1. Ms. Johnson’s class is having a pizza party. If there are 14 students and 7 pizzas cut into 8 slices, what answer choice represents the fraction of one pizza that each student receives? If someone can give me an equation to solve to get the answer for this. Or Help me ...

*November 20, 2016*

**Math**

1. What is 0.68 written as a simplified fraction?

*November 20, 2016*

**Math**

32-19=13 32+19=51

*November 20, 2016*

**Math**

(x+3)/2 >= (2-x)/-2 x+3 >= x-2 3 >= -2 true for any x

*November 20, 2016*

**math**

So, b-c = 10/4 b+c = 5

*November 20, 2016*

**Linear Programming - The Graphical Method**

Just graph each boundary line for the constraints, then evaluate the function at each vertex.

*November 20, 2016*

**Calc III**

take a look here http://math.stackexchange.com/questions/1572835/finding-the-max-and-min-values-for-a-surface-on-region-r and I think you will be able to get going. Google can also provide many other examples.

*November 20, 2016*

**ST**

enter your data here to see the details. http://www.zweigmedia.com/RealWorld/LPGrapher/lpg.html

*November 20, 2016*

**Calculus**

work this one just like the last. But time = distance/speed, rather than cost=distance*rate.

*November 20, 2016*

**Calculus**

If the cable comes out of the river x meters from the point directly opposite the factory, then the cost is c = 3?(x^2+2000^2) + 1(4500-x) so, find where dc/dx=0 The answer is 4500-x.

*November 20, 2016*

**Math help fast**

x^2/2 - 2x = 16 ...

*November 20, 2016*

**Maths**

Find where the curves intersect. Clearly, at x=2, since y(2) = 22 = 11*2 I was wondering about the "hence". So, the area in question has two parts. That under the line and that under the curve: a = ?[0,2] 11x dx + ?[2,3.7988] 10+8x+x^2-x^3 dx = 22 + 27.2556 = 49.2556...

*November 20, 2016*

**maths**

x^2 - 8x - 20 = 0 (x-10)(x+2) = 0 ...

*November 20, 2016*

**Calculus**

x=cos^2t y=ln(sint) dy/dt = cost/sint dx/dt = -2cost sint dy/dx = dy/dt / dx/dt = (cost/sint)/(-2cost sint) = -1/2 csc^2(t) d^2y/dx^2 = d/dx(dy/dx) = d/dt (dy/dx) / dx/dt = (-csct * csct cott)/(-2cost sint) = 1/2 csc^2(t) cot(t) * sect csct = 1/2 csc^3(t)

*November 20, 2016*

**Maths**

L1 has slope 0 L2 has slope ?3 see what you can do with that.

*November 20, 2016*

**Math**

I assume you meant (5x-2)/4 + 1/2 = (3y+2)/2 (7y+3/3) = x/2 + 7/3 Cleaning things up a bit, you have 5x-6y = 4 3x-42y = -8 See what you can do with that.

*November 20, 2016*

**Math**

If it was x, then .4*x + .6*8 = 1.0*6 x = 3

*November 20, 2016*

**Math! Help asap**

interesting, since 124 = 4*31 Where did you get the 19? "over by"? Try just "over" Better yet, use real math (5+-[31])/2 Though I have never seen [] used to denote square root before.

*November 19, 2016*

**Math! Help asap**

It does not factor over the rationals, since the discriminant b^2-4ac = 100+24 = 124 is not a perfect square. Use the quadratic formula to find the roots, or maybe there's a typo.

*November 19, 2016*

**math**

http://www.jiskha.com/display.cgi?id=1479538720

*November 19, 2016*

**math**

5*2x - (4x+6x) Looks like a zero profit.

*November 19, 2016*

**algebra**

Nope. You correctly got that x-(-3) = x+3 Work y the same way.

*November 19, 2016*

**Algebra, 8th Grade mathematics**

note that x^2-1 = (x-1)(x+1) x^3-1 = (x-1)(x^2+x+1) x^4-1 = (x-1)(x^3+x^2+x+1) so, 3^251-1 = (3-1)(3^250+3^249+...+3^1+1) So your sum is just (3^251-1)/(3-1)

*November 19, 2016*

**Maths**

each minute mark is 1/60 of a circle for the minute hand: 6° So, the minute hand has gone 37*6 = 222° around. In the meantime, the hour hand, starting at 2:00 (60° along its path), has advanced another 37/60 * 1/12 = 37/720 of a circle. So, the hour hand has moved ...

*November 19, 2016*

**FUNCTIONS HELPPPPP????**

The g(x) I suggested was a last-ditch effort to come up with some function using f1,f2,f3. You repeatedly refused to specify what you meant when you said Determine an equation for this function "this function" indicates that there is some function you want to create ...

*November 19, 2016*

**math**

43C9 = ?

*November 19, 2016*

**math - business**

highest profit is at the vertex, when x = -b/2a = 4/.01 = 400 P(400) = 600

*November 19, 2016*

**algebra/pre-calc - please help**

If we use x as the number of days since the start of the year, build each piece with a y=mx+b section, where the price starts a t b and the line has slope m ($/day) January is y = 10 + 2/31 x February is 12 - 3/28 (x-31)

*November 19, 2016*

**blah blah blah**

a+b=15 10b+a = 10a+b - 27 69 = 96-27

*November 19, 2016*

**math**

what, you can't plug in h=1 or h=6? and online you write 5e^(-0.4h)

*November 19, 2016*

**algebra**

.40*.80 = .32 so, .20x = .18 x = .9 so, win 90% of the remaining games.

*November 19, 2016*

**Algebra 2**

well the slope is -3/4, and the point slope is y-k = m(x-h) so plug in your numbers. It does not matter which point you choose for (h,k).

*November 19, 2016*

**algebra 2**

usually a complex number is written a+bi, and coefficients come before variables. I know it is tempting to put the ?5 last so it does not get confused with following numbers, but that's just orthography. here, a is zero, so just bi: 6?5 x^4 i

*November 19, 2016*

**algebra 2**

me too Usually the i comes last, though.

*November 19, 2016*

**math**

I recall such rates in about 1964, but it was, of course, compound interest.

*November 19, 2016*

**Pre-calculus**

This one is easier if you work on the right side. (sin(x-y)/cos(x-y)) / (sin(x+y)/cos(x+y)) (sinxcosy-cosxsiny)/(cosxcosy+sinxsiny) ------------------------------------- (sinxcosy+cosxsiny)/(cosxcosy-sinxsiny) Expand those products, and you will be able to factor out some (sin...

*November 19, 2016*

**Physics**

none, except against air resistance. For a given force at takeoff, the mass affects the acceleration.

*November 19, 2016*

**Math**

Think about y=x^2 x can be either plus or minus and produce the same y value. Sp, as y grows on one side of the axis, it also grows on the other side. Plot a few points.

*November 19, 2016*

**java program**

you mean display the code? Surely the payroll system displays its own information.

*November 19, 2016*

**Algebra**

well, 3n^2+5n-100 = (3n+20)(n-5)

*November 19, 2016*

**maths**

AC = 1/2 AB PC = 1/2 AC = 1/4 AB

*November 19, 2016*

**Math**

81 = 3*27 so, the number is 4*27

*November 19, 2016*

**math**

if the scale factor is s, then P2/P1 = s A2/A1 = s^2

*November 19, 2016*

**Maths**

You can start here. Once you know the side length of the triangle, you can get its area. https://owlcation.com/stem/Inscribed-Circles-and-Equilateral-Triangles-7-Hard-Geometry-Problems-and-Solutions

*November 19, 2016*

**math**

If the %ages are based on the gross, then she saves (628-148.90-628(.045+.08))*.10 = $40.06 If they are based on after-tax income, then she saves (628-148.90)(1-(.045+.08)))*.10 = $41.92

*November 18, 2016*

**Precalculus**

D: all reals R: all reals > 0

*November 18, 2016*

**chemistry**

f" = -36sin(6x) f' = 6cos(6x)+c f'(0) = 6+c = -5, so c = -11 f' = 6cos(6x)-11 f = sin(6x)-11x+c f(0) = c = -3 f = sin(6x)-11x-3 f(?/3) = sin(2?)-11(?/3)-3 = -11?/3 - 3

*November 18, 2016*

**Math**

boy, you don't give much away, do you? The average value is ?[a,b] f(x) dx ------------------ b-a So, what didn't work? ?[-1,2] 4x^3-3x^2 dx = x^4-x^3 [-1,2] = (16-8)-(1+1) = 6 6/3 = 2 So, where is f(x)=2? 4x^3-3x^2=2 x ? 1.137

*November 18, 2016*

**Math**

see the related questions below. Just use your function instead.

*November 18, 2016*

**English**

#1 means that you are in sustained flight higher than the clouds #2 implies that in a while you will come back down, as in "The cow jumped over the moon." #3 Lots of explanations online. You might start here: http://www.grammarbank.com/impersonal-pronouns.html

*November 18, 2016*

**Calc**

http://www.jiskha.com/display.cgi?id=1479256552

*November 18, 2016*

**Math help please**

yes

*November 18, 2016*

**Math help please**

geez -- impatient much?

*November 18, 2016*

**Math help please**

TeX is not much good here, as you can see.

*November 18, 2016*

**Math help please**

a pizza place charges $5 per pizza, with a $7 delivery fee. How much does a delivery order for x pizzas cost?

*November 18, 2016*

**math**

try just posting a problem without copying all the surrounding text, eh? Don't make us figure out the question as well as the answer. Clean it up and post it again. Maybe just one question. Learn from its solution and try more on your own.

*November 18, 2016*

**Math**

If the length is x, then 2(x + 2x-8) = 104

*November 18, 2016*

**Math**

since y=2x-5, 4x-(2x-5) = 7 Now solve for x, and then you get y.

*November 18, 2016*

**Maths**

The yacht should take a bearing of the harbour, and then sail on that heading. Not sure what 065T means, but I assume it's 65° clockwise from True North. If so, then the heading back to the harbour is found via Label the diagram as follows: H = harbour P = point of ...

*November 18, 2016*

**Physics**

conserve momentum: 3500(45) + 1600(-25) = (3500+1600)v

*November 18, 2016*

**Functions**

so, what is your work? Show how you did it.

*November 18, 2016*

**Functions**

Oh come on. Just plug in their definitions: g(x) = f2(x)-f3(x) = (1/8(x+16)^2-98)-(2x+24) = 1/8 x^2 + 2x - 90 f1(x)=0 is stupid, as it contributes nothing.

*November 18, 2016*