Thursday
September 29, 2016

Posts by steve

Total # Posts: 44,235

Math
looks good to me
September 20, 2016

Math
well, how many ounces in 6 lbs? Divide that by 5oz/apple to get the no. of apples.
September 20, 2016

math
no
September 20, 2016

6th Grade Maths
45/(2 x 4.7 - 4.4) x 6 = 54
September 20, 2016

Advanced Functions 12
not sure what the secant lines mean. At x = 1/2, they all pass through 1/2 f(x) = (3 - 1/4)/2 = (1/2,11/8) That won't get anywhere near the tangent line, no matter what other point you choose. I suspect there is something left unsaid here.
September 20, 2016

math
42
September 20, 2016

Math
well, the list of running times is 5,7,8 can you not figure the range of such a list?
September 20, 2016

calculus need help
Really. Ha you know that the solution of y" + y = 0 is y = a sinx + b cosx Now use the method of variation of parameters: We now have y1 = sinx y2 = cosx The Wronskian of {sinx,cosx} is -1 u1 = ∫cosx tanx dx = ∫sinx = -cosx u2 = -∫sinx tanx dx = ∫...
September 20, 2016

math
cannot access files stored on your computer. duh.
September 20, 2016

Math
(1/3 ft)/ (1/6 yd) but, since 1 yd = 3 ft, you have = (1/3 ft) / (1/2 ft) = (1/3) / (1/2) = 2/3
September 20, 2016

maths
You have three unknowns, and only two equations. Here is what wolframalpha.com says: c+s+h = 100 5c + s/10 + 2h = 100 http://www.wolframalpha.com/input/?i=solve+c%2Bs%2Bh+%3D+100,+5c+%2B+s%2F10+%2B+2h+%3D+100 There is no unique solution, but if you play around, you can see ...
September 20, 2016

algebra
correct
September 20, 2016

algebra
what do you mean by "write a full" ? Note that as x grows by 1, y grows by 2. SO, start wity y = 2x Now adjust that so that the values agree with those in the table.
September 20, 2016

Math
5.25/.75 = ?
September 20, 2016

Math
Why have two variables? Each function has a flat fee and an hourly rate. The only variable is the time. You want the time to be such that the two cost are equal. Where did you get the 2? You're not multiplying by the number of service calls. Each service call has a flat ...
September 20, 2016

Math
well, st = u + v/2 now just one more step to go...
September 20, 2016

math
again? See your first post, or the related questions below
September 20, 2016

Math
if moving in the same direction as the bus, just add the speeds. If moving in the opposite direction, subtract her walking speed from the bus's speed.
September 20, 2016

Math
No. It grows 144/7 = 20.57 inches. Think about it. It takes 7 days to grow 6 inches. 24 is a little more than 3*7. So, it will grow a little more than 3*6 = 18 inches. You need to work on your reading, too...
September 20, 2016

Math
If it were 21 days, since 21 = 7*3, it would grow 6*3 = 18 inches. 24 is not quite that simple. It grows (24/7) * 6 = 144/7 inches why did you multiply 6 by 4? You cannot multiply days by inches. The units make no sense. Instead, you want to convert days to inches, using the ...
September 20, 2016

math
see earlier post
September 20, 2016

Math
draw the vectors. Since they are perpendicular, the resultant is just the hypotenuse of the triangle.
September 20, 2016

Jewelry
Seems like I read about this necklace in a mystery novel...
September 20, 2016

math
solve as you would an equation. The only thing to watch for is to change the direction of the inequality when multiplying by a negative quantity. 2(3x−6)>=5x-10 6x - 12 >= 5x-10 6x-5x >= -10+12 x >= 2 So, pick out all the values at least 2. To be sure, ...
September 20, 2016

math
you ask us to show our work in solving the problem. Why not show your work and how it went wrong? I suspect a typo, since 5(0) - 10 = -5 That makes your equation 2(3x-6) = -5 So, does -5 work? 2(3(-5)-6) = 2(-15-6) = 2(-21) = -42 Nope. Now you try the others to see whether any...
September 20, 2016

Math
fifty seven million three hundred seventy-three thousand two hundred eighty-four = 57373284 Now just move the decimal place as needed.
September 20, 2016

Algerbra
well, 1.7x10^2 = 0.17x10^3 Now just add 'em up
September 20, 2016

Math
review the conditions for the series to exist. In this case, it will exist for x=0, so we want y = ∑anx^n y' = ∑nanx^(n-1) y" = ∑n(n-1)anx^(n-2) The DE then says ∑n(n-1)anx^(n-2) + x*∑nanx^(n-1) + ∑anx^n = 0 ∑n(n-1)anx^(n-2...
September 20, 2016

math - eh?
You want to try that again in English?
September 20, 2016

Math Question
why are there 4 empty squares? Or are some of the numbers used more than once?
September 20, 2016

maths
c+s+h = 100 5c + s/10 + 2h = 100 There is no unique solution if that is all you are given. And the plural of sheep is sheep, not sheeps, and certainly not sheep's!
September 20, 2016

Math
just multiply 5 by the desired value(s)
September 20, 2016

physics
no friction means no force no force means no acceleration no acceleration means constant velocity.
September 20, 2016

maths calculus need help plz
this is a pretty standard linear DE. Read about its method of solution here: https://answers.yahoo.com/question/index?qid=20120112065721AA0UzfI If you're still confused, there are lots of explanations on why the method works so well.
September 20, 2016

Math
recall that the angles of a triangle sum to 180°. So, you must have 2x+5 + 6x-5 + 7x = 180
September 20, 2016

ALGEBRA
(212-32) = 180 SO, there are 180°F for 100°C So each °F is 5/9 as big as a °C each °C is 9/5 as big as a °F That should help you get started.
September 20, 2016

Math
really? How many times larger is 20 than 4? How did you get that answer? Do the same thing for your numbers. Remember that you divide the values and subtract the powers. What do you get?
September 20, 2016

Matg
Luckily, the 3' width of the rolls divides either dimension of the room, so you don't have to worry about buying extra rolls for the leftover width. Carpet Master: (720*30 ft^2) * 1roll/6ft^2 * $1/roll = (720*30*1/6*1) = $3600 Flooring King: (720*30 ft^2) * 1roll/36ft^...
September 20, 2016

physics
oops: watch the units (66.4km/hr) / (t hr) = 66.4/t km/hr^2 I'd say: total distance: 99.5(t - 24/60) avg speed = distance/time 99.5(t - 24/60)/t = 66.4 t = 1.202 distance is thus 99.5(1.202 - 24/60) = 79.8 km
September 20, 2016

Maths Constructions
you can construct a right angle by making a perpendicular bisector of a line segment. That's one of the very first constructions you did. Mark the right angle as point B. Then, mark off side BA. Then from A, set the radius to 6.2cm and draw an arc that intersects the ...
September 20, 2016

Math
Let C = {4,5} Then A = {2,C,4} They are all incorrect, and it should be clear why. What are your reasons?
September 20, 2016

Algebra
since distance = speed * time, (s-50)(5) = (s+50)(4.5) That's some fast plane!
September 20, 2016

Precalculus
For the inside argument, the domain is all real numbers except where the denominator is zero. If your denominator is -x^2-4x-10 it is never zero, since the discriminant is 16-40 < 0 So, the domain is (-∞,∞) Now, for the log to be defined, we need 10+|x+6|/(-x^2-...
September 20, 2016

Algebra
g = b+16 g+13 = 2(b+13) now just solve for g and b.
September 20, 2016

math
no, 2+2 = 4
September 20, 2016

science
Since PV=kT, PV/T is constant. So, you want T where (1.41)(25.1)/T = (1.82)(18.7)/353
September 19, 2016

Calculus
yes, k=2
September 19, 2016

Pre algebra
-12/(3(-8+(-4)^2-6)+2) -12/(3(-8+16-6)+2) -12/(3(2)+2) -12/8 -3/2
September 19, 2016

Math
Do you mean 8*4^(2x) - 4 = 53 8*4^(2x-4) = 53 either way, isolate the 4^? and then take log of both sides to get x by itself on the left.
September 19, 2016

math
a. The power of an electric appliance is given by the formula P=I^2R, where I is the current and R is resistance. Use this information to explain how you can use radicals to determine the current if the power and the resistance is given. b. Find the current in amperes if a 40-...
September 19, 2016

MATH
can't see, but I'd bet that it's √2 times the value shown.
September 19, 2016

Math please help
It does not matter! Pick any number you like. Just be sure to use it both top and bottom. I know you have trouble with math, but I was hoping you could understand English...
September 19, 2016

Math please help
starting with 5/6, multiply both top and bottom by the same number, such as 3: 5/6 = 15/18 Now fill in the other blanks.
September 19, 2016

Grade 10 Math
As always, draw a diagram. She is standing 3 ft from where the wire is attached to the ground. Using similar triangles (in inches), the height h can be found by 69/36 = h/180
September 19, 2016

Algebra
Ab^2 = -18 A(3^(1/5))^2 = -18 A(3(2/5)) = -18 A = -18 * 3^(-2/5) = 18 / 9^(1/5) = 2 * 9^(4/5) It would be nice if you showed your work ...
September 19, 2016

Algebra
Ab^-3 = -6 Ab^2 = -18 divide to get rid of the A's and you have b^-5 = 1/3 b^5 = 3 b = 3^(1/5) Now use that to get A
September 19, 2016

math
24 = 8*3 32 = 8*4
September 19, 2016

Physics
how long does it take a penny to rise and fall, starting at 3.0 m/s? v = 3 - 9.8t double that, and that's how long the first penny has been dropping before the 2nd gets back to the top of the well.
September 19, 2016

algebra
since you are given a point and a slope, start with the point-slope form: y-5 = 3(x-1) Now just rearrange things to get what you need.
September 19, 2016

Algebra
I don't know whether you worked it right, since you didn't show what you did, but you got the right answer
September 19, 2016

Math
ummm, 300/10 = ?
September 19, 2016

math
1,60 2,30 ... Consider the factors of 60. It should not take long to fine the right ones.
September 19, 2016

Math
did you try listing the first few? The pattern should be clear 1 = 1 1+3 = 4 1+3+5 = 9 1+3+5+7 = 16 Does the sequence 1,4,9,16,25,36,... look familiar?
September 19, 2016

sciences
first, decide which are acids, and which are bases. Then, what does the litmus paper do in each case?
September 19, 2016

Algebra
y=3x-7 That may not be the one you want, however. Try n=making your own, considering that cost = flat_fee + rate * time
September 19, 2016

math
one connects two equal things, the other describes how they are unequal. equation vs inequality
September 19, 2016

Math
v = π*25*3 as for the time, check the units: (cm^3) / (cm^3/min) = min
September 19, 2016

Math
change all the fractions to decimals and compare them
September 19, 2016

Math
well, 2720/6 = 453 2/6
September 19, 2016

physics
balance momentum: .020 * 150 = 2v
September 19, 2016

maths trignometry
I assume you mean √((seca + 2sina)/(seca-2sina)) = (sina+cosa)/(sina-cosa) well, clearly, the first thing to do is square both sides: (seca + 2sina)/(seca-2sina) = [(1+2sina*cosa)/cosa] / [(1-2sina*cosa)/cosa] = (1+sin2a)/(1-sin2a) see where that takes you, after ...
September 19, 2016

Math, please help! :)
Ms. Sue has a point. The list will have to be 5, 9, 12, x, 13, 17 or 5, 9, 12, 13, x, 17 Since there are six number, the median will be the average of the middle two. (12+16)/2 = 14 but 16 cannot be inserted in between 12 and 13, and if it goes after 13, then the median is 12.5
September 19, 2016

algebra - theory of numbers
google is your friend. You might want to start here: https://en.wikipedia.org/wiki/Divisor_function
September 19, 2016

Trigonometry
But anyway, if arctan(2) is the solution to a problem, just leave it as-is. That way you have the exact answer, instead of just an approximation. And, it's clear what the value is. Saying that θ = 1.107 does not give much insight into where it came from.
September 19, 2016

Trigonometry
short answer: no you can always use graphical or numeric methods to find the zeros of the function f(x) = tan(x) - 2 Then there are Taylor Series, etc. Your best bet is just to use a calculator (online or mechanical), just as you would to fine log(12) or e^3.1 or any other ...
September 19, 2016

Trigonometry
you evidently need to review the definitions of the basic trig functions. In this case, tanθ = 75/100
September 19, 2016

math
well, just look. They added just one textbook, and the weight grew by 1 kg. Clearly the extra textbook weighed 1 kg. Or, algebraically, 3d+3t=9 3s+2t=8 subtract and you get rid of the d's, leaving 0d+1t = 9-8 t=1
September 19, 2016

Maths
3*39 = 3^2 * 13 now turn that into a list of all factors
September 19, 2016

maths
with a little expansion, you can arrive at sin(5x)+sin(7x) = 4sin(x) cos^2(x) (2cos(2x)-1) (2cos(2x)+1) now the roots are easy to find.
September 19, 2016

mathematics help
unusual to have complex coefficients, but x^2 = -16j = 16cis(3π/2) x = ±4 cis(3π/4) = ±4 (-1/√2 + 1/√2 j) = ±2√2 (-1+j)
September 19, 2016

science
the mass does not matter. a = (20m/s)/(5s) = (20/5) m/s^2
September 19, 2016

mathematics need help
since the slope is 3, start with x = t y = 3t since the y-intercept is -2, y = 3t-2
September 19, 2016

calculus help me asap
Here's what wolframalpha.com ends up with: http://www.wolframalpha.com/input/?i=derivative+y%5E6%3Dtanh%5E-1(tan%5E-4(4x%5E2%2By%5E2)%5E2)%5E9 That's as you typed it. I interpreted it as http://www.wolframalpha.com/input/?i=derivative+y%5E6%3Dtanh%5E-1(tan%5E-4((4x%5E2...
September 19, 2016

calculus help me asap
this is just stupid. y^6 = tanh^-1(u)^9 6y^5 y' = 9 tanh^-1(u)^8 * 1/(1-u^2) du/dx where u = tan^-4(v^2) and v = 4x^2+y^2 = cot^4(v^2) du/dx = 4 cot^3(v^2) (-csc^2(v^2)) (2v dv/dx) dv/dx = 8x + 2yy' mash all that together and solve for y' I see little to be gained ...
September 19, 2016

Maths
well, 40 = 5*8 55 = 5*11
September 19, 2016

Maths
not sure what the :||+|| means and it appears you have too many = signs but yes, 2*2 = 4
September 19, 2016

math
3d+2t = 8 3d+3t = 9 clearly, t=1
September 19, 2016

Math 115
for 100 < P, C(P) = 100 + 0.72(P-100) or C(P) = P - 0.28(P-100)
September 19, 2016

Math 115
for 30 < t <= 40, D(t) = D(30) = 2 for 40 < t <= 65 D(t) = 2 + (1/60)(t-40)
September 19, 2016

math
60/x = sin30°
September 19, 2016

Math115
t is in minutes, and D is in miles. Since the speed is given in mi/hr, you have to divide that by 60 to get mi/min
September 19, 2016

Math115
why all the words? Just say D(t). I'll do the first piece. See what you can do with the rest. Starting from t=0, having gone 0 miles so far, D(t) = 0 + 4/60 (t-0) for 0 <= t <= 30 = 1/15 t That may seem cumbersome, but therein lie hints for the other parts.
September 19, 2016

Algebra
since the slope m is constant, (13+5)/(3-r) = m You have not included the value of m, but once you divulge that secret, you can find r.
September 18, 2016

math
since the model is 1/16 as big, just divide all the dimensions by 16: boat: (17/16) ft car: (20/16) ft You might want to express those in inches
September 18, 2016

Math
x^2 - 2x it's as valid as any other expression.
September 18, 2016

Physics
v = 9.8t s = 100 - 4.9t^2
September 18, 2016

College Algebra
why the inconsistency? Either say 4 less than t less than or equal to 6 or, my favorite, 4 < t <= 6 For that piece, we have C(t) = 4 for 4 < t <= 6 see what you can do with the others.
September 18, 2016

Math
how come you can say + but cannot say - ???? 1/4 + 2/7 + 11/12 - 3/4 = 2/7 + 11/12 - 1/2 = 24/84 + 77/84 - 42/84 = ...
September 18, 2016

Math
(81+11 - 8*4)*1 = 60
September 18, 2016

math
355-2 < v < 355+2
September 18, 2016

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