Wednesday
February 10, 2016

Posts by Steve

Total # Posts: 37,540

Plz My Maths
This is just like the cloth problem. If there are m people and each one received n, then mn = 6500 (m+15)(n-30) = 6500 Now just solve for m and n. Why Do You Capitalize Every Word? It Is Rather Distracting. BUT NOT QUITE AS MUCH AS ALL CAPS, EH?
January 6, 2016

MATH
or, just start with what you are given: a point and a slope. Ding ding - use the point-slope form of the line: y+2 = -3/2 (x-3) now just rearrange stuff, and you will get Reiny's equation.
January 6, 2016

math
a = 3c b = a-6 b = 4d a+b+c+d = 39 (a,b,c,d) = (18,12,6,3)
January 6, 2016

math
if the figure is a parallelopiped, the bases have the same area. So, if the dimensions given are x,y,z, I'd say each base has area 2*6 = 12. your presentation is rather cryptic...
January 6, 2016

math
well, 1/4 = 2/8, so what do you think?
January 6, 2016

Maths
since cost is unitprice(p) times length (q), pq = 200 (p-2)(q+5) = 200 p = 10 Birr/m q = 20 m
January 6, 2016

Math of Investment
(1+.55/2)^(2n) = 2 I guess. Not sure of what your notation means.
January 6, 2016

math
what does "decreased by one of its one fourth" mean? decreased by 1/4, or decreased by 1/4 of its value? either n = d+5 or n = d-5 so, the new value is either (d+5)/(d+10) or (d-5)/(d+5) now equate that to whatever your weird statement implies.
January 6, 2016

math
cone: 1/3 πr^2 h hemisphere: 2/3 πr^3 sum: πr^2/3 (h+2r) Now just plug in your values.
January 6, 2016

Math
since the slope of the line is 1/2, tanθ = 1/2 = y/x. Now draw that triangle in QIII and you can see that cosθ = x/r = -2/√5
January 6, 2016

Math
since the median is the center value, at most half of the numbers can be positive.
January 6, 2016

Algebra 1
clearly it is not a whole number. Now you should note that the fraction is the ratio of two integers.
January 5, 2016

Geometry
5/x the enlargement ratio is newsize / oldsize
January 5, 2016

Math
You want a constant ratio, so (7+x)/(4+x) = (12+x)/(7+x) x = ?
January 5, 2016

Algebra
correct
January 5, 2016

math algebra 2 using inverse variables
no idea what an inverse variable is. you have listed two variables and their values. So what?
January 5, 2016

Algebra 2
in one year, 2.44 * 1.005^12 In n months, it will cost $5.00, when 2.44*1.005^n = 5.00
January 5, 2016

Geometry
Take a look at the angle bisector theorem. AB/AC = BD/DC
January 5, 2016

maths
factor out the 3, and you have x^2+x+24 = 0 No real solutions, since the discriminant is negative Use the quadratic formula to get the complex roots.
January 5, 2016

math
42
January 5, 2016

Algebra 1
NOOO It's (4,-7)! I explained how that pair fits both equations. try plugging in your numbers and see that they are waaaaaayyyy off!
January 5, 2016

Algebra 1
So, with the correct equations, you'd have to add them to eliminate y: 4x-y=23 7x+y=21 ------------- 11x=44 x=4 then plug that into either equation to figure out y.
January 5, 2016

Algebra 1
clearly there is a typo in the equations, or the answer key is wrong. The equations you gave have solution x = -2/3 y = -77/3 which you can check by plugging those values into both equations. (4,-7) is a solution to 4x-y=23 It is also a solution to 7x+y = 21, not the equation ...
January 5, 2016

Algebra 1
clearly you need to review the material on elimination. Google will provide lots of examples.
January 5, 2016

Algebra 1
elimination means that you manipulate the equations so that one of the variables is eliminated. Since the left sides are equal to the right sides, subtracting the left sides from each other and the right sides from each other gives a valid equation. You can see that if you ...
January 5, 2016

Algebra 1
just subtract one from the other to eliminate y: -3x = 2 Now you can get x, and then plug that in to get y.
January 5, 2016

Log maths help me plz
Hmmm. b = a^(3/2) d = c^(5/7) a = b^(2/3) c = d^(7/5) a-c=9, so b^(2/3) - d^(7/5) = 9 I assume we want integer solutions, so let's list the squares of cube roots and the 7th powers of 5th roots: n n^(2/3) 1 1 8 4 27 9 64 16 125 25 216 36 n n^(7/5) 1 1 32 128 243 2187 1024 ...
January 5, 2016

PHYSICS
assuming you meant speed, that would be 15*2π/2 = 15π m/min
January 5, 2016

Equation help plz
The equation is a circle with radius √14, centered at (-5,12) So, the minimum value of x^2+y^2 is the point on the circle nearest the origin. Since the center of the circle is 13 units away, the closest point on the circle is 13-√14 units away.
January 5, 2016

math
r^3 = 4375/35 = 125, so r=5 Now use that as you need to.
January 5, 2016

Math
LCM(8,7)=56, so the ages are in the ratios of 35:56:24 Since those three numbers add up to 115, they are also the ages.
January 5, 2016

Math
well, geez -- how about, um, substituting? You see that x = y-6, so substitute that into the other equation and you can then find y: y = 6-3(y-6) ...
January 5, 2016

Math 11
of what?
January 5, 2016

Calculus
y=1, and x=2 Bogus limits. Fix one or the other. In any case, the radius is 10-y and v = pi r^2 h
January 4, 2016

calculus
My bad. Using discs, the integral is v = ∫[0,1] π(R^2-r^2) dy where r = 1-√(1-y) and R = 1+√(1-y) v = ∫[0,1] π((1+√(1-y))^2-(1-√(1-y))^2) dy = ∫[0,1] 4π√(1-y) dy = 8π/3
January 4, 2016

calculus
Why don't you show your work? Using shells, try v = ∫[0,2] 2πrh dx where r = x and h=y=2x-x^2 v = ∫[0,2] 2πx(2x-x^2) dx = 8π/3 Using washers, we have v = ∫[0,1] π(R^2-r^2) dy where r = 1-√(1-y^2) and R = 1+√(1-y^2) v = &#...
January 4, 2016

Calculus
You're right. The boundaries are not clear to me either. http://www.wolframalpha.com/input/?i=plot+y%3D2sinxcosx%2C+y%3D2cosx
January 4, 2016

Trigonomentry help plz thanks
This is a challenge analytically, but using the graph it is easy: http://www.wolframalpha.com/input/?i=%28cosx%29^7%2B%28sinx%29^4%3D1 Coming up with the solutions -π/2, 0, π/2 is easy, but showing there are no others is tough.
January 4, 2016

Bionomial expansion help agn #thanks
The third term is C(6,2)(√x)^4(1/√y)^2 = 15x^2/y
January 4, 2016

Calculus help plz i do not no it at all
I seriously doubt it. Take a look at how wolframalpha interprets that: http://www.wolframalpha.com/input/?i=integral+x%E2%88%9A%282%2B3%E2%88%9C%28x^3%29%2F%28x^6%E2%88%9Ax%29%29 Maybe you can play around with your syntax till you get what you want.
January 4, 2016

Calculus help plz i do not no it at all
Do you mean x√(2+3∜(x^3)/(x^6√x))? I doubt it. How about some clear text with matched parentheses? If there are higher roots, just spell them out, as cuberoot(x), 4throot(x), etc.
January 4, 2016

Word problem help plz
oops. 85-41=44 Still no joy.
January 4, 2016

Word problem help plz
I guess by inverted you mean the digits are switched. So, if the father's age is xy and the son's age is ab, then we have 10x+y+10a+b=99 10a+b+10y+x=72 10x+y-(10b+a)=28 http://www.wolframalpha.com/input/?i=solve+10x%2By%2B10a%2Bb%3D99%2C+10a%2Bb%2B10y%2Bx%3D72%2C+10x%...
January 4, 2016

Word problem help plz
what is an "inverted age"?
January 4, 2016

Algebra 1
there is no solution to the given system.
January 4, 2016

Algebra
slope is 7, so y-0 = 7(x-0) or, y=7x
January 4, 2016

ALEGEBRA 1
clearly, y=y now substitute in the two different definitions. Draw the two lines. The solution is where they intersect.
January 4, 2016

Math Complicated
no, clearly it does not. The long bar over the sum means to evaluate everything under the bar, and then take the root of the result. Think of the long bar as a set of parentheses, as I showed above.
January 4, 2016

Math Complicated
No long lines online, but you can use parentheses: √(5 + 8 +24) = √37 since 5+8+24=37
January 4, 2016

Math
just add powers in products, and subtract in divisions: (6x^4)(4y^2) / [(3x^2)(16y)] = (6*4)/(3*16) * x^(4-2) * y^(2-1) = 1/2 x^2 y = x^2y/2
January 4, 2016

Math
Not sure what you mean by "make 3/5 to 21/25" 3/5 * 7/5 = 21/5
January 4, 2016

Geometry
yes, it is a "normal" trapezoid; it just means that its two non-parallel sides are not the same length. So, all you have to do is show that two of the sides of ABCD are parallel, and the others, not. Clearly, AB and CD are parallel, since they have the same slope. So...
January 4, 2016

physics
well, F = ma = 4200(3 + 10)
January 4, 2016

geometry
the surface area is just the sum of the two ends and the curved side. a = 2πr^2 + 2πrh = 2π*4*(4+12) Now just evaluate that on your calculator.
January 4, 2016

Math
whenever you have problems like this, draw a right triangle. In this case, you want a triangle with one angle x. If the sides are a,b,c with b opposite angle x, and c the hypotenuse, then sin(x) = b/c Now, the angle whose cosine is b/c is the other acute angle of the triangle...
January 4, 2016

Maths
3 times as many men means it takes 1/3 as long, right?
January 4, 2016

Mathematics
take a look at the point-slope form of a line, and you will see that yours is y-35 = 3/4 (x-40)
January 4, 2016

engineering maths. need answer asap
just conserve momentum before and after the collision. You then have 15*10 + 30*5 = (15+30)v
January 4, 2016

math
so, what's the difference between the area of a 12x12 square and a circle of diameter 12?
January 4, 2016

Conversions
all you have to do is add 273.15 to get the K temperature. That's not going to make much difference in 10^9 degrees.
January 3, 2016

Geometry
well, since all opposite sides of any parallelogram are parallel, it's not clear just what your question is.
January 3, 2016

Math
the answer cannot be 0,0. You are asked to find the coordinates of the vertices. Since the center of dilation is (0,0) and the scale factor is 4, just multiply all of the coordinates by 4.
January 3, 2016

math
since distance=speed*time, 2x = 4(x-4) x = 8 so, the distance is 2*8 = 16 miles each way
January 3, 2016

math
One way is to find the point on 13x+4y=32 which is at a distance of 4 from the line 3x+4y=28. Since the distance from (h,k) to ax+by+c=0 is |ah+bk+c|/√(a^2+b^2) and we know that k = (32-13h)/4, we have |3h+32-13h+28|/5 = 4 |-10h+60| = 20 h = 4 or 8 so, k = -5 or -18 ...
January 3, 2016

Math
correct. If you got that, I think your work must have been fine. It's due to the chain rule.
January 3, 2016

Math
domain of all exponentials is (-∞,∞) Range of a^x is (0,∞), so I'm sure you can adjust that as needed here. you know that the domain of √x is [0,∞), so now you just have to adjust to make sure that x-2 >= 0. As for the range, just recall ...
January 3, 2016

Math
Oops. I meant (c)
January 3, 2016

Math
Looks like (d) to me no constant difference no constant ratio
January 3, 2016

Math
beginning: at rest during: in circular motion end: at rest
January 3, 2016

Math
Ivan: 4.25+1.25m Vicky: 5.75+0.75m I+V: 4.25+1.25m+5.75+.75m = 10.00+2.00m = 2(5+m)
January 3, 2016

Math
well, you know that x=y-6, so, um, uh, substitute? y = 6-3(y-6) y=6 Now you can find x.
January 3, 2016

mathematics
well, 1.5 * 115 = 172.5 but that's not the $130 you say she has. Better fix up the question and post it as yo received it.
January 3, 2016

Maths equation plz help urgently
If you mean 10^x = 100, then clearly x=2, since 100=10*10 = 10^2
January 3, 2016

trigonometry
Since there are two angles of 55°, the vertex angle is 70°. So, each of the two matching sides has length 54/cos55° Now you can add up the sides to get the perimeter.
January 3, 2016

algebra
you have a point and a slope (2), so use the point-slope form: y-6 = 2(x-0) Now just rearrange the terms as needed.
January 3, 2016

MATHS
21 15/20 - 18 4/20 = ?
January 3, 2016

maths lit, egd, civil , business studies
maybe teach one of them?
January 3, 2016

Math
6 9/12 - 2 4/12 - 1 9/12 = ?
January 3, 2016

math 7th grade connections
d+g/h = 35+19/6 = 35+3.17 = 38.17 (d+g)/h = (35+19)/6 = 54/6 = 9 59+13n = 59+13*44 = 631 Something tells me you have trouble with the order of operations.
January 3, 2016

Science
Draw a triangle. If the plane's speed due north is v, then 60^2 + v^2 = 240 direction θ such that sinθ = 60/240
January 3, 2016

geometry
You need to explain a bit more how the angles and sides are positioned.
January 2, 2016

MATHS
Clearly the large cube is 6x6x6. So, how many 2x2x2 cubes is that?
January 2, 2016

Algebra
what? No ideas? The fee is constant.
January 2, 2016

Calculus help plz
I suspect a typo. Wolframalpha indicates that it cannot be done with elementary functions: http://www.wolframalpha.com/input/?i=integral+%28%28x%2B1%29%2F%28x-1%29%29^%281%2F3%29%2F%28x%2B1%29dx If I got it wrong, and only the (x+1) is in the cube root, it can then be done, ...
January 2, 2016

math
naturally, 1-.2 = .8
January 2, 2016

physcis
of course, you have to watch the units (2π√80 cm)/(10 m/s^2) mixes up cm and m. Convert cm to meters by (2π√80 cm)(1m/100cm)/(10 m/s^2) = π√80/500 s^2 = 0.056 s^2 An odd quantity, s^2
January 1, 2016

math- HELP!
Oww! My bad! Should have caught my typo. 26π*200 in/min The ridiculous speed of less than 1/2 inch per minute should have caught your eye!
January 1, 2016

math- HELP!
26π in/rev * 200rev/min = 26π/200 in/min w is not 200. It is 200*2π radians/min
January 1, 2016

Math
You have the equations x+y=−2 y=13x+2 You know it is a 2-D graph The lines intersect at (-2/7,-12/7), so none of the choices listing a different intersection can be right. That leaves only (A). Now you just have to check to see whether the lines pass through the named ...
January 1, 2016

Math
so, did you graph it? Which choice matches your findings?
January 1, 2016

Math
(x + 1/x)^2 = 3 x^2 + 2 + 1/x^2 = 3 x^4 - x^2 + 1 = 0 x = ±i^(1/3), ±i^(5/3) using i^(1/3), we have x^37 = i^12 i^(1/3) = i^(1/3) x^31 = i^10 i^(1/3) = -i^(1/3) x^47 = i^15 i^(2/3) = -i i^(2/3) x^26 = i^8 i^(2/3) = i^(2/3) x^63 = i^21 = i x^9 = i^3 = -i Looks ...
January 1, 2016

Math
5^3x = 65 3x log5 = log65 3x = log65/log5 x = log65/3log5 I assume you meant 2^(2x+3) = 80 (2x+3)log2 = log80 2x+3 = log80/log2 x = (log80/log2 - 3)/2
January 1, 2016

science
google is your friend. 1st hit solved the problem.
January 1, 2016

computer programming
use the function to calculate the nth fib #, and return its value. Then loop for p=1..5 and print each value returned.
January 1, 2016

Calculus need help
do you mean (x+x^3)/y or x + x^3/y ? It makes a difference
January 1, 2016

Math
(a) clearly, a = (5x+15)(31-2x) (b) I think you can graph a parabola (c) values for zero area (d) use what you know about parabolas (e) ditto (f) since this is a real-world situation, negative lengths are meaningless. So, D = [-3,31/2] R = [0,<value at vertex>]
January 1, 2016

MATHS
see related questions below.
December 31, 2015

Algebra
well, 1/12 of w is w/12 so, what's 4 more than that?
December 31, 2015

Math
y = (7/8)^x log(y) = x log(7/8) ... y=log12x 10^y = 12x ... and similarly for the last one.
December 31, 2015

Calculus
Each slice of water is a rectangle. Its length is 10. If the water has depth y, then the width of the rectangle is √(1 - (1-y)^2) = √(2y-y^2) Now you have to figure the water's depth (h), and the height to pump each slice of water is 2-y. So, you have to ...
December 31, 2015

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