Friday

September 30, 2016
Total # Posts: 44,247

**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*

**Educational Tech**

input and output

*August 23, 2016*

**Methametical literacy**

she's 60 km ahead when he starts he's going 20km/hr faster. 60/20 = 3 hrs to catch up

*August 23, 2016*

**math ASAP**

x/(x+6) = 7/9 9x = 7(x+6) 9x = 7x + 42 2x = 42 x = 21 so, x+6 = 27

*August 23, 2016*

**Math**

see related questions below

*August 23, 2016*

**Math**

(5600*.95)*1.10 = .95p

*August 23, 2016*

**math**

6 = 2*3 so, 3 times as far as he went in 2 hours.

*August 23, 2016*

**maths**

since cos(a+b) = 0, a+b = pi/2 so, b = pi/2 - a and sin(a-b) = sin(a-pi/2+a) = sin(2a-pi/2) = -sin(pi/2 - 2a) = -cos(2a) or, since a = pi/2 - b = -cos(2(pi/2-b)) = -cos(pi-2b) = cos(2b)

*August 23, 2016*

**Geometry**

just use the distance formula for each segment.

*August 23, 2016*

**Math**

if the first vertex is at (1,0), then the others are at (cos 2kπ/7, sin 2kπ/7) for k=1..6

*August 23, 2016*

**Math**

$5.50 no matter how many hours. Now, if you want an hourly rate, well, duh -- divide the money by the time: $/hr

*August 23, 2016*

**physics**

series: R = 6 parallel: R = 1/6 Other arrangements will produce values in between those.

*August 23, 2016*

**Maths**

well, with those two roots, f(x) = (x+2)(x-3) so expand that and you can see what p and q must be.

*August 23, 2016*

**Math**

5 is 3 * 5/3 So, the distance is (5/3)(189)

*August 23, 2016*

**algebra**

google your question. Much faster than waiting around here: https://www.google.com/#q=metric+ton

*August 23, 2016*

**Urgent help! Physics**

Vx = v cosθ Vy = v sinθ h(t) = Vy*t - 5t^2 ball stops when h=0 ball has traveled Vx * t along the ground.

*August 23, 2016*

**Algebra**

n = 6+4 "exceeds" and "more than" indicate addition. See what you can do with q.

*August 23, 2016*

**Math**

2/5 + 1/5 + 1/x = 1 x = 5/2

*August 23, 2016*

**Math**

Just list the possibilities. You know there are 36 total outcomes. How many fit the conditions? R B R-B 1 1 0 1 2 -1 1 3 -2 2 1 1 2 2 0 2 3 -1 2 4 -2 ... 4 6 -2 Then divide the successes by the total of 36

*August 23, 2016*

**Math**

so, she picked 2*35 + 15

*August 22, 2016*

**maths**

If there are x liters of 25/L then we have the value of the milk as 25x + 30(60-x) = 1600

*August 22, 2016*

**math**

distance = speed * time, so (1/2 hr) * (y mi/hr) = y/2 mi

*August 22, 2016*

**Math**

4/(5+4+y)

*August 22, 2016*

**phy**

the waves are a sin(x) and b sin(x-k) add them up and you have a sinx + b(sinx cosk - cosx sink) = (a+b*cosk)sinx - (b*sink)cosx This is basically just Asinx + Bcosx which can be reduced to a single sine wave of amplitude √(A^2+B^2) See a nice discussion at https://en....

*August 22, 2016*

**pre caluclus**

since you give only one focus, I assume it's a parabola. Since both points lie on the line y=2, the parabola opens horizontally. Recall that y^2 = 4px has focus at (p,0) and vertex at (0,0) Your parabola has obviously been shifted up by 2, so it will be (y-2)^2 = 4px Your ...

*August 22, 2016*

**Math**

just recall that supplementary angles add to 180, so 4x+3 + 3x-5 = 180 Now just solve that for x.

*August 22, 2016*

**Algebra 1**

the first step is usually to clear all the fractions by using the LCD. In this case 12. Do that and you have z/3 - 3 = z/4 + 7 4z - 36 = 3z + 84 z = 120 Or, you can collect terms as usual, and then clear fractions z/3 - 3 = z/4 + 7 z/3 - z/4 = 10 (1/3 - 1/4)z = 10 1/12 z = 10 ...

*August 22, 2016*

**algebra**

These are all difference of squares or sum/difference of cubes. You need to be able to recognize such values, and apply the formulas: a^2-b^2 = (a-b)(a+b) a^3±b^3 = (a±b)(a^2∓ab+b^2) For example, 16x^4a-y^8a = a(16x^4-y^8) = a(4x^2+y^4)(4x^2-y^4) = a(4x^2+y...

*August 22, 2016*

**Algebra**

since V is proportional to r^3, V(2r)/V(r) = 2^3 gather all the constants into a single k, and you have V(r) = kr^3 V(2r) = k(2r)^3 = k(2^3)(r^3) = 2^3*V(r)

*August 22, 2016*

**math**

one every polynomial of degree n has exactly n solutions.

*August 22, 2016*

**Algebra 1a**

no kidding. In big letters on the home screen it says Post homework questions online a general whine is not a homework problem.

*August 22, 2016*

**Math**

2450 - 2549 but I must say I do not care for the way the question was worded.

*August 22, 2016*

**Algebra**

√(3x-6) = 4 3x-6 = 4^2 = 16 3x = 22 x = 22/3

*August 22, 2016*

**Algebra**

3c^2 - 5c - 7.8 = -2.2 3c^2 - 5c - 5.6 = 0 Now just use the quadratic formula

*August 22, 2016*

**Math**

correct

*August 22, 2016*

**Algebra**

well, you know that y = 3.8x+2.2 so use that in the other equation to get 4.5x - 6.7(3.8x+2.2) = 8.6 4.6x - 25.46x - 14.74 = 8.6 now it's easy, right? Then, once you have x, use that to get y.

*August 22, 2016*

**Math**

1st step: subtract 5.514 from both sides: 9.2x = 152.72 I guess you can figure out what's next, no?

*August 22, 2016*

**Algebra**

65.9 - 32.4k/9.9 = 13.3k 65.9 - 3.28k = 13.3k Think you can handle that now?

*August 22, 2016*

**Absolute Value**

all correct.

*August 22, 2016*

**Algebra**

why all the words? You showed the math. Just solve the way you normally would; don''t let the fractions confuse things. 1/2.75 = 1/3.2 - 1/x 1/x = 1/3.2 - 1/2.75 1/x = (2.75-3.2)/(3.2*2.75) x = (3.2*2.75)/(2.75-3.2) = 8.8/-0.45 = -19.556 Or, just convert to decimals at...

*August 22, 2016*

**math**

sheet area: 32*24 buttons area: 64 * π * 3.5^2 now just subtract

*August 22, 2016*

**algebra 1 please help**

just plug in your numbers: (81+125)/2 * 75

*August 22, 2016*

**MATHS (EQUATIONS)**

.8x + .9y = 240

*August 22, 2016*

**Maths**

ooops. Misplaced the decimal point. I'm sure you can fix it.

*August 22, 2016*

**Maths**

juice: 9% of 120L = .09*120 = 1.08L And so on

*August 22, 2016*

**Maths**

it's a line: http://www.wolframalpha.com/input/?i=-3x%2B2y%3D-6

*August 22, 2016*

**American Government**

nope - that's what the Supreme Court decides

*August 22, 2016*

**math**

well, 36000000 * 6 = 600^3

*August 22, 2016*

**Math**

same answer using the exterior angles, which sum to 360°

*August 22, 2016*

**science**

straight lines have a constant slope. That is often written y = kx In this case, the quantities have different names, but it should be clear which choice is correct if you just use your names instead.

*August 22, 2016*

**science**

hint: it's called a half-life for a reason.

*August 22, 2016*

**algebra**

i = kpt, so if p is the same, i/t = pk is constant. Thus, you want i such that 960/6 = i/7 That is, since 7 is 7/6 as big as 6, the interest will be 7/6 * 960

*August 22, 2016*

**math**

If the cardboard is x by y, then xy = 160 2(x-4)(y-4) = 144 Now just solve for x and y.

*August 22, 2016*

**ALGEBRA**

time = distance/speed, so if he rode x miles on the bike, x/43 + (281-x)/3 = 7 solve for x, and then x/43 is the time on the bike.

*August 22, 2016*

**maths**

If the number is x, then x = 10t+5 so, 10t+5 = 7(mod 11) 10t = 2(mod 11) so, which multiple of 10 leaves a remainder of 2 when divided by 11? How about 90 = 88+2? So, t=9 95 = 10*9+5 = 11*8+7

*August 22, 2016*

**Math 2**

That's phi, not phe Ø-1 = 1/Ø Ø^2-Ø-1 = 0 Ø = (1±√5)/2 pick the positive value

*August 21, 2016*

**physics**

time = distance/speed( m / m/s = s) avg velocity is totaldistance/totaltime so, that gives (95.0+95.0)/(95.0/1.26 + 95.0/3.61)

*August 21, 2016*

**Calculus**

you know that sin(x) is negative in QIII and QIV sin(.294) = 0.29 so, you want the numbers π+.294 and 2π-.294

*August 21, 2016*

**Calculus**

You know that lim sinu/u = 1, so sin2x/5x = sin2x/2x * 2/5

*August 21, 2016*

**Algebra**

If you meant |t| -2 = -1 |t| = 1 then B

*August 21, 2016*

**Maths Mensuration**

2π*3 * 14

*August 21, 2016*

**Maths Mensuration**

A(r) = πr^2 A(r+h) = π(r+h)^2 now subtract.

*August 21, 2016*

**Mathematics**

then f(0) = -1 But then, that may not be what you were after ... Hard to say, since you did not. But it does factor easily, right? It's just Algebra I

*August 21, 2016*

**chemistry**

So, first step: decide on the partial equations. There's a good discussion here: http://chem-guide.blogspot.com/2010/03/balancing-chemical-equations.html

*August 21, 2016*

**chemistry**

how many moles in 5g of Al? The equation says you will use 3/2 that many moles of Ag2S So, convert that back to grams of Ag2S of course, the amount of jewelry will be proportional to its surface area, not its volume.

*August 21, 2016*

**maths**

Hmmm. 24 = 2*10 + 4 24 = 2*11 + 2 You want to try that again?

*August 21, 2016*

**Calculus**

The two pieces are of length x and 100-x Since a square has four equal sides, A(x) = (x/4)^2 + ((100-x)/4)^2

*August 21, 2016*

**Math**

15mn = 15nm = (15n)m (15n)m/m = 15n

*August 21, 2016*

**maths**

but it's not!

*August 21, 2016*

**control structures**

I assume you can do the I/O The calculation is discount = (purchases > 30000) ? 0.10 : 0.02; drop that into a while loop and The I/O and you're done

*August 21, 2016*

**pre-cal**

draw a diagram review your trig functions. You will see that the height h can be found using h cot48 - h cot64 = 22

*August 21, 2016*

**Math**

area goes up as the square of the scale, so you would have 180 * 100^2 m^2 Now just convert that to hectares

*August 20, 2016*

**Math**

again? the real question is why you keep tossing in spurious apostrophes!

*August 20, 2016*

**Math**

a+w+c = 25 25a+400w+50c <= 2500 You will get a range of fruits. Or, just start with 6 watermelons cost $24 so, what can you buy with the other dollar? Not enough to make up 25 fruits. So, consider 5 watermelons for $20 Now you have $5 for the other 20 fruits. and so on

*August 20, 2016*

**Algebra**

the domain is all reals except where the denominator is zero. So, when is x^2-49 = 0 ? For the hole, note that 2x+14 = 2(x+7)

*August 20, 2016*

**algebra**

it hits the ground when the height is zero. So, just solve 256-16t^2 = 0 (16-4t)(16+4t) = 0 ...

*August 20, 2016*

**PHYSIC**

work = force * distance so, plug in your numbers.

*August 20, 2016*

**MATHS**

try using some easy numbers first. if buying 10 lbs, his scale says he is only getting 11 lbs. His selling scale says he is selling 9 lbs. See what you can do with that. Looks to me like he's losing money. Unless somehow the buying/selling is from the customer's ...

*August 20, 2016*