Saturday
December 10, 2016

Posts by Steve

Total # Posts: 47,042

math
must be all 9's, eh?
October 29, 2016

Math probability
well, what is the chance that the 1st sock is blue? Having removed it, what is the chance that the 2nd is blue? The number of blues and the number of socks have both been changed by removing the 1st blue sock. Now just multiply.
October 29, 2016

math
a = F/m, so plug in your numbers.
October 29, 2016

Math Help
It means the number of elements in the set. Clearly you have not studied your material.
October 29, 2016

Math Help
so, do you know what n(a) means? If you do, this cannot be a hard problem.
October 29, 2016

math
ha ha if you can read, just put it into math. If the river's speed is x, then since time = distance/speed, 4/(2+x) = 1/(2-x)
October 29, 2016

math
google is your friend https://www.quora.com/How-do-you-calculate-the-number-of-squares-in-an-n-x-n-square-grid
October 28, 2016

maybe math
If Reiny is right, then to simplify, -1/8 + 1/8^2 = -8/8^2 + 1/8^2 = -7/8^2 or, 2 ∑ -2^k/8^2 k=0 How's that for simple? And all positive exponents!
October 28, 2016

Math Derivative
yes. The good old chain rule. It helps to write them as fractions, so things cancel out: dg/dx = dg/dh * dh/dx I know they usually tell you to avoid thinking of derivatives as fractions, but they really are. It's the same with parametric functions, x(t) and y(t) dy/dx = (...
October 28, 2016

Calculus
a scalar multiple just distributes as in a complex number: a(x+yi) = ax+ayi (1/2)<-3,7> = <(1/2)(-3),(1/2)(7)>
October 28, 2016

Physics
conserve total angular momentum.
October 28, 2016

Calculus
well, y' = -2/(3y), so y" = 2/(3y^2) y' = ...
October 28, 2016

Calculus I
show what you did. This kind of problem always works out that the fencing is divided equally among lengths and widths. So, the entire array will have dimension (50/3) by (50/4) Each pen will be (50/9) by (50/8) Start with 3x+4y = 100 a = xy = x*(100-3x)/4 then find x such that...
October 28, 2016

Math (Confused)
9*10^3 * 9*10^4
October 28, 2016

Math (Finding Vertical Tangent)
looks to me like there is a vertical tangent at x = 2pi/3
October 28, 2016

Algebra
75% is correct. There is a mistake somewhere in the problem or the answer. Could it be that they won 6 and lost 8? That would make the answer 6/14 instead of 6/8.
October 28, 2016

Chem
1 mole occupies 22.4L at STP so, you will have 17.8*22.4L PV = nRT
October 28, 2016

Algebra
cost = revenue to break even So, what is the cost for x pencils?
October 28, 2016

Math
need for what? and how much is a "dash"?
October 28, 2016

Math
if x mL were lost and replaced, then .80(250-x) + .40x = .72*250
October 28, 2016

Math - forget it
Oops - my bad. I misread it. Embershy is correct
October 28, 2016

Math
23/40 - 23/30 = 23(1/40 - 1/30) = 23(3/120 - 4/120) = 23(-1/120) = -23/120 Note above that 23/30 is not 11/15.
October 28, 2016

Math
.30*8 + 1.00x = .35(8+x)
October 28, 2016

Chemistry
The total mass of the solution is x where .0910x = 19.0
October 28, 2016

maths
660 is nowhere close. You want the circumference of a circle. You don't say whether 220 ft is the diameter or the radius, or even the circumference. If the diameter, your new larger circle has diameter 220+6 = 226 If the radius, your new larger circles has diameter 440+6...
October 28, 2016

easy Math
well width * length = area so, ...
October 28, 2016

easy math
(6/2)^2
October 28, 2016

algebra
6.50 per hour means the hourly charge will be 6.50h so, now what do you think?
October 28, 2016

Calculus
cosh(3x) = cosh(2x+x) = cosh2x coshx + sinh2x sinhx ...
October 28, 2016

BASIC TECH
How about some English? With the aid of compass and ruler bisect a line of 12 cm. The length of the line does not matter for the construction. Draw the line AB. Open the compass to more than half the length of AB. From A, draw an arc From B, draw an arc The two arcs (if long ...
October 28, 2016

Maths
x^2-36 and 2x^2-15x+18 so what?
October 28, 2016

MATHS URGENT
9/u + 4u = -12
October 28, 2016

MATHS URGENT
ok ok never mind looking at the related questions. 7^(2x-1) = 7^(2x)/7 4*7^(x-1) = 4*7^x/7 so, doing what they suggested, you have u^2/7 + 4u/7 - 1/14 = 0 Think you can handle that?
October 28, 2016

Physics
v = at and acceleration is m/s^2, not m/s
October 28, 2016

math
3C-243
October 28, 2016

Math
since time = distance/speed, 10/(v+5) = 8/(v-5)
October 28, 2016

9th grade algebra (factoring)
all correct. Good job.
October 27, 2016

math check answers
how did you arrive at that amount? The monthly interest rate is only .035/12
October 27, 2016

Math
Add up the total of all the ages. You have for x people, 41(x-2) + 86+84 = 45x
October 27, 2016

math
x: v*cos(theta) y: v*sin(theta)
October 27, 2016

Physics
see the related questions below. Think of polar coordinates, and place the starting point at (r,0)
October 27, 2016

Math
768 = 3*2^8
October 27, 2016

Math
well, there's no equation, but the derivative of that expression is just 6(x^2+y^2)^5 * (2x + 2yy')
October 27, 2016

Math
Implicit Differentiation for (x^2+y^2)^6
October 27, 2016

calculus
see your previous post - in the related questions below
October 27, 2016

math
x(1 - 1/4 - (3/4)(3/5)) = 3600
October 27, 2016

Math
Hydrogen
October 27, 2016

Math (Derivative)
The definition is the limit of f(x+h) - f(x) -----------------      h That is where the subtraction comes in.
October 27, 2016

Math (Derivative)
uh -- from the definition of the derivative. Better reread it.
October 27, 2016

math
Oops - my bad. I was looking for volumes. The overlap is the area of the circular base of the cone (pi r^2) and the circular base of the hemisphere (pi r^2). Subtract it twice, once for each solid.
October 27, 2016

math
surely you have the formulas for finding the volumes of these solids. Just add 'em up. What do you get? Show work if you get stuck.
October 27, 2016

Economics
If you borrow $1000 from the bank, and the effective annual rate is 9.4% with monthly compounding. How much do you pay after 2 years?
October 27, 2016

ALGEBRA 2
surely your text has a section on linear programming, where it explains problems just like this one. Assign variables write the constraints define the objective function evaluate at all the vertices of the region.
October 27, 2016

maths
(4x-5)(x-5)=175
October 27, 2016

Math
p = y+5 r = 2(p+y) 10y+20p+25r = 13350
October 27, 2016

Math
you really gotta work on your typing. volume of tank: π/6 * 10^3 cm^3 fill rate: π*20^2*2 cm^3/s now divide to get the time.
October 27, 2016

math
note the differences. The amount subtracted is 1,2,3,4,...
October 27, 2016

Algebra 1
It's always a good feeling when that happens.
October 27, 2016

Algebra 1
yes, except for the typo y = 3/7 x + 38/7
October 27, 2016

Math
well, each side is 8, so ...
October 27, 2016

Math
54 - 8*4 = ?
October 27, 2016

Information Systems Technology
so, first step: make a loop to read the input, and exit when the employee id = -999
October 27, 2016

Math
in 3 hours, A is 180 miles ahead. B is going 12 mi/hr faster, so how long to make up the 180 miles?
October 27, 2016

Algebra I
you have two points. The slope is 10/6 = 5/3. Now, using he point-slope form, you have y-3 = (5/3)(x-4) y = 5/3 x - 20/3 + 3 y = 5/3 x - 11/3 Or, solving for y = mx+b 3 = 4m+b -7 = -2m+b and solve for m and b.
October 27, 2016

Math
Nope - V = k/T
October 27, 2016

Algebra
well, f(x) = k/x so, plug in your numbers to find k.
October 27, 2016

Geometry Help?
#1. Nope - 3^2+4^2 = 25 #2. Nope - the hypotenuse is 10, not the leg #3 ok #4 ok #5 nope - look carefully
October 27, 2016

Maths
well, the altitude is a/2 √3
October 27, 2016

math
hint: it's x + 2x-13 = 77
October 27, 2016

math
well, can't you check it to see whether it works?
October 27, 2016

math
2c + 4(c+3) = 24
October 27, 2016

tri
40-20 degrees ?? 40°, or 20°, or 40°20' in any case, if the base is b, then sin(θ/2) = (b/2)/320 = b/640
October 27, 2016

Algebra
You must mean R', which is clearly all the even numbers. So, not C. Look closely.
October 27, 2016

Physics honors
not sure what unit "a" is. If it's 7 m/s, then since 1'45" = 105 seconds, it should be clear.
October 27, 2016

math
read up on the birthday problem: the chance that two will share a birthday.
October 27, 2016

Maths
so, it was solved earlier, using the wrong equation. Fix it and follow the same steps! It works out better this time. Not only is there a single real root, but a single double root!
October 27, 2016

Maths
see related questions below
October 27, 2016

MATH HELP PLEASE
depends on the scale, which you have neglected to provide. It is B if the scale is 1cm:50
October 27, 2016

maths
37.5 = 75/2 = 60 + 30/2 so, tan 37.5 = tan 75/2 = (1-cos75)/sin75 = (1-cos(60+15))/sin(60+15) ... you get the idea
October 27, 2016

Math
1,2 ok 3,4 wrong pay attention to the minus signs.
October 27, 2016

Math
you need to ask some specific questions. No one here can review your whole text for you. Probably wouldn't help anyway. If you can't figure it out from your text, you probably won't be able to do it here. Go online and google problems like the ones you have to do. ...
October 27, 2016

Math
since you have no examples, google the subject - you will find many many solved problems online.
October 27, 2016

Math
the volume is just the area of the trapezium times its length.
October 27, 2016

math
1/3 * 36 = ?
October 27, 2016

maths
consider the angle θ subtended by the arc he has run on a track of radius r. The location of the point at time t is s*t where s is his speed in units of distance/time. If we lay out the track so he started at (r,0) and ran in a counterclockwise direction, then at time t, ...
October 27, 2016

Algebra
since there is zero cost, what you charge is all profit, right?
October 27, 2016

Computer Science
display "enter name, number: " read s (name,num) = split(",",s) while (num-- > 0) {   display name } use the language of your choice
October 27, 2016

trigonimetry
The sides of the triangle are 65,69,80 (sums of radii). So, you can probably find the medians given the sides, yes?
October 27, 2016

Math
s + s-30 + s-30-20 = 220
October 27, 2016

Easy Algebra Equation
5-2x-12=14 watch those - signs ...
October 26, 2016

Algebra
if a linear equation, then a line. Any point on the line has coordinates that satisfy the equation.
October 26, 2016

Algebra
since the coefficients are rational, the roots come in conjugate pairs. So, the roots are 3-i, 3+i, √2, -√2 f(x) = (x-(3-i))(x-(3+i))(x-√2)(x+√2) = (x^2-6x+9+1)(x^2-2) = ...
October 26, 2016

math
Ali does 3/2 the work, so he'd take 2/3 the time.
October 26, 2016

Maths
since the largest reading is 20, you have x+20+20 = 3*16 x = 8 for the smallest.
October 26, 2016

Math
test post, right?
October 26, 2016

Algebra
75x < 280+40x
October 26, 2016

Calc
f '(s) = 10s − 4s^3 f(s) = 5s^2 - s^4 + C f(3)=7, so 5*9-81+C = 7 Do the same for the 2nd one, but use both specified conditions to find the constants.
October 26, 2016

Math
21 = 7*3 ...
October 26, 2016

Algebra
9z^2-36z+34 = 0 9(z^2-4z+4) = 2 (z-2)^2 = 2/9 ...
October 26, 2016

math
b(b+4)/2 = 35
October 26, 2016

  1. Pages:
  2. <<Prev
  3. 9
  4. 10
  5. 11
  6. 12
  7. 13
  8. 14
  9. 15
  10. 16
  11. 17
  12. 18
  13. 19
  14. 20
  15. 21
  16. 22
  17. 23
  18. Next>>