Thursday
September 3, 2015

Posts by Damon


Total # Posts: 21,879

Math
13% is so much more than 6% that the compounding will not catch up for many years.
June 10, 2015

Math
1.06^4 = 1.26248 *2000 = 2524.95 so earned 524.95 0.13 * 4 =.52 .52 * 2000 = 1040 so earned 1040.00 go with the 13 % simple
June 10, 2015

Chemistry
how many Joules do you need? Joules needed = specific heat * mass * change in temp then watts * seconds = Joules needed
June 9, 2015

Chemistry
C * m (60-40) = C * 50 (40-20) so m = 50 grams or .050 Kg
June 9, 2015

History
Should I laugh or cry?
June 9, 2015

Calc 1
sure looks like it to me
June 9, 2015

Calc 1
Hey, you can google too :)
June 9, 2015

Calc 1
not necessarily http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&cad=rja&uact=8&ved=0CEgQFjAI&url=http%3A%2F%2Fwww.mathsisfun.com%2Fcalculus%2Fdifferentiable.html&ei=2wt3VbzLIMGasQXEoIEI&usg=AFQjCNG-Oqx8EjGrCBl7-c8WA0YYFZ28ag&sig2=WquSfxU_It3cBOBGKCGExg&bvm=bv....
June 9, 2015

Calc 1
True, if more then not a function http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0CDMQFjAC&url=http%3A%2F%2Fwww.milefoot.com%2Fmath%2Fcalculus%2Flimits%2FFindingAsymptotes12.htm&ei=ZAt3Ve-jC4mQsAXlt4HgDQ&usg=AFQjCNHZjboUch1fdELGYXBuIZC-Tnu_rg...
June 9, 2015

Calculus 1
well, if x = .99 I get 1.50 if x = .999 then 1.500 that is because numerator = (x-1)(x+2) denominator = (x-1)(x+1) so what we really have is (x+2)/(x+1) which is 1.5 at x = 1 It is true that the original function is undefined at x = 1
June 9, 2015

physics
They are brakes. after 5 sec at constant v Vi = 20 v = 20 + a t where t is total time - 5 v = 0 when t = 8 so 0 = 20 + a (8) a = -20/8 = - 5/2 so v = 20 - (5/2) t = 20 - (5/2)(time - 5)
June 9, 2015

Math
11 with vanilla + 11 with chocolate = 22 , right
June 9, 2015

Calc 1
y at x = 5 = a then y^2 = 25 all right when x = 5
June 9, 2015

math
total N = 330 + 900 = 1230 Total E = 640 + 370 = 1010 so sqrt (1230^2 + 1010^2)
June 9, 2015

Calc 1
nope, what if y = L (x-a)/|x-a|
June 9, 2015

Math
pi is actually about 22/7 This problem is a lot harder than it looks because you should really pack the discs in a hexagonal pattern but I suspect the best we can do is put squares around the circles. 100 /14 = 7.14 so 7 lengthwise 60/14 = 4.28 so 4 that direction 7 * 4 = 28 ...
June 9, 2015

math trigonometry
I have no reason to believe it is true.
June 9, 2015

SCIENCE
A to B speed = 300m/170 seconds velocity = speed if that direction is + then A to C distance = 300 + 100 = 400 average speed = 400/230 but total displacement = +300 - 100 = 200 so'=average velocity = 200/230
June 9, 2015

math
I do not think so. Sketch a graph.
June 8, 2015

Physics
x = 1.40 t^2 - .0505 t^3 at t = 0, x = 0 at t = 1.91, x =1.40 * 1.91^2 - .0505 * 1.91^3 = 4.755 meters so 4.755 meters in 1.91 seconds = 2.5 m/s do the others the same way, find out how far it went in the time interval and divide by the time interval
June 8, 2015

statistics
5/15 * 4/14
June 8, 2015

MATH
x/10 = 37/8 so x = 370/8 (370/8)/16 = 370/128 = 2 114/128 = 2 57/64
June 8, 2015

math
2* (1/2) pi (1) + 2*3 maybe ?
June 8, 2015

Math help please.
7 yes 8 A because -3 * -2 = +6
June 8, 2015

Math help please.
6)-2r(8r+5) A)-16r^2+5 B)-16r+10 C)-16r-10r** D)-16r-10 Nah, -16 r^2 - 10 r probably c but a typo
June 8, 2015

Math help please.
7^4/7^2 = 7^2 = 7*7 = 49 right
June 8, 2015

Math help please.
4) 50 A)0 B)5 C)1 D)-5 Perhaps you mean 5^0 but anything^0 = 1
June 8, 2015

Math help please.
3) 4^4/4^6 4 - 6 = -2 4^-2 = 1/4^2 = 1/16 A)-16 B)16 C)1/16 D)-1/16
June 8, 2015

Math help please.
2) h^14/h^5 14 - 5 = 9, not 19
June 8, 2015

Math help please.
1) x^9/x^2 = x(9-2) = x^7
June 8, 2015

maths
if the second hand moves 180 degrees, that is half a minute .5 min (360 degrees/60 min) = 3 degrees
June 8, 2015

Calculus
Oh, go with what Steve said.
June 8, 2015

Calculus
profit = p(x) - C(x) = 50-.01 x - 10 - 2x = 40-2.01 x max at x = 0 I bet you have a typo though.
June 8, 2015

math
well one way is a parabola write a parabola that goes through (4,1) (6,1.5) and (8,6) first (4,3) (6,0) and (8,0) Y1 = 3(x-6)(x-8) /(4-6)(4-8) = 3(x^2 -14 x + 48)/ 8 second (4,0)(6,1.5)(8,0) Y2 = 1.5 (x-4)(x-8)/(6-4)(6-8) = -(1.5 x^2 -18 x +48)/4 third Y3 = 6(x-4)(x-6)/(8-4)(8...
June 7, 2015

math
whoops, I dd it for 300 of fence, not 200
June 7, 2015

math
if two internal petitions the 4 x needed for cross fencing + 2 L needed for length P = 4 x + 2 L =300 or L = 150 - 2 x A = x L = x (150 - 2 x) = 150 x - 2 x^2 if you know calculus: dA/dx = 0 at max = 150 - 4 x so x = 150/4 = 37.5 then L = 150 -2*37.5 = 75 AREA = 37.5*75 = 2812...
June 7, 2015

COLLEGE MATH
I do not know what level of math you are at. If calculus then dC/dx = 0 at min = .4 x =96 so x = 240 If Algebra 2 level then complete the square to find vertex .2 x^2 - 96 x = -12095 x^2 - 480 x + 240^2 = - 60475 x^2 - 480 x + 240^2 = - 2875 (x-240)^2 = -2875 so x = 240 and C...
June 7, 2015

Another math related question
4/10 * 7/15 = 14/75
June 7, 2015

Calculus
you have P = 2 x + 154/x BUT you took the derivative incorrectly P' = 2 -154/x^2 so for min or max 0 = 2 - 154/x^2 or x^2 = 77 NOTE d/dx (1/x) = -1/x^2
June 7, 2015

physics
any acceleration is down the slope, perpendicular to the force we are interested in. That normal force is the component of weight normal to the hill surface which is m g cos 25
June 7, 2015

physics
If two capacitors are in parallel, they hold more charge for a given voltage. We know that C = Q/V here C1 = Q1/V C2 = C2/V C1 + C2 = (Q1+Q2)/V so final C = C1 + C2 In other words, if in parallel, add capacitances because you add charges per unit voltage
June 7, 2015

to damon
You are welcome - good luck !
June 7, 2015

algebra
ah ham you know Pascal's triangle so you know binomial theorem after all now call a = 4 y call b = x then (a+b)^4 = a^4 + 4 a^3b + 6 a^2b^2 + 4 a b^3 + b^4 which is 256 y^4 + 256x +6 (4y)^2 x^2 etc
June 7, 2015

maths
sin PQR = 300/600 = 1/2 so PQR = 30 degrees that is 30 degrees south of west or 60 degrees west of south which id a compass bearing of 180 + 60 = 240 degrees clockwise from north cos 30 = RQ/600 RQ = 520 m
June 7, 2015

algebra
no imagine (x-y)^2 it is not x^2 - y^2 but x^2 - 2 x y + y^2 You need the "binomial theorem" If you have learned it your problem is straightforward, follow the recipe. If you have not had it in your course, I feel for you because you will have to do it step by ...
June 7, 2015

algebra
(x^4 y^5)^5 = (x^4)^5 (y^5)^5 = x^20 y^25
June 6, 2015

Physics
do the fall first v = g t 44 = 9.81 t t = 4.49 seconds falling now the up part Vi = 24.4 v = Vi - g t 0 = 24.4 - 9.81 t where t is time rising t = 2.49 seconds upward so 4.49 + 2.49 seconds
June 6, 2015

Physics
Yes, your wording indicates that you need help. You not only have to heat the water to 100 deg C You have to BOIL IT as well ! so look up the specific heat of water, call it C then LOOK UP THE HEAT OF VAPORIZATION of water. then heat in = 2 * specifc heat * (100-37) + 2 * heat...
June 5, 2015

6th Grade Probability
1/4 of the times you play (1/4)36 = 9
June 5, 2015

Physics
wavelength = twice string length to get node at each end and bulge in middle. L = (1/2) wavelength wavelength = speed * period = speed/frequency so L = (1/2) v/f
June 4, 2015

Algebra
check below http://www.jiskha.com/display.cgi?id=1433381900
June 4, 2015

Physics
You are welcome.
June 4, 2015

Physics
The tension and mass density determine the speed of the wave along the string. The input frequency is the wave frequency wavelength = speed * period = speed/frequency so frequency, tension and mass density right
June 4, 2015

Physics
A yes B yes C No D yes I agree.
June 4, 2015

Algebra
L^2 + w^2 = d^2 (d-3)^2 + (d-8)^2 = d^2 d^2 - 6 d + 9 + d^2 -16 d + 64 = d^2 d^2 - 22 d + 73 = 0 d = [ 22 +/- sqrt(484 - 292) ] / 2 d = [ 22 +/- 13.9 ] / 2 d = 17.9 or 8.1 8.1 is impossible if the area is 84 so d = 17.9 ------------------- check then w = about 10 and L = about...
June 4, 2015

Math
66 = 2*33 = 2 * 3 * 11 99 = 3 * 33 = 3 * 3 * 11 20 = 2*10 = 2 * 2 * 5 etc, boring
June 4, 2015

Math
look at b^2 - 4 a c if +, then two intercepts if 0, then just grazes the x axis, one intercept if -, then never hits the axis, imaginary roots only if a x^2 + b x + c = 0 then - (a x^2 + b x + c) = 0 is the same because +0 = -0
June 4, 2015

math
sin^4⁡x-cos^4⁡x = (sin^2 x+cos^2 x)(sin^2 x -cos^2 x = 1 (sin^2 x - cos^2 x) = 2 sin^2 x - 1
June 4, 2015

physics
d1 = (1/2)(5)(64) Vi = 0 + 5 * 8 d2 = Vi * (12-8) d = d1 + d2
June 4, 2015

math
one leg of right triangle is 150 other leg is 120 sqrt (150^2+120^2) = 192
June 3, 2015

Social Studies
You are welcome.
June 3, 2015

Social Studies
Write your thoughts and perhaps a teacher will help. hints - where is the Statue of Liberty ? What words are on it? How many buffalo are around, not to mention native tribes ? Wicked difficult growing cotton and rice and stuff under the snow.
June 3, 2015

Math
slope = (13-10)/(5-4) for example = 3 so T = = 3 S + b 1 = 3 + b b = -2 so T = 3 S - 2
June 3, 2015

Math
sorry - I used 15 mph instead of 18
June 3, 2015

Math
at 12 it tskes t so d = 12 t at 15 it will take .25 leas time d = 15 (t-.25) so 12 t = 15 t - 15/4 3 t = 15/4 t = 5/4 d = 12(5/4) = 15 miles
June 3, 2015

Math
120 = x t so t = 120/x 120 = (x+5)(t-1/3) or 120 = (x+5)(120/x - 1/3) 120 (3)(x) = (x+5)(360 - x) 360 x = 360 x -x^2 + 1800 -5 x x^2 + 5 x - 1800 = 0 (x-40)(x+45) = 0 x = 40
June 3, 2015

Math
t is time after 12 noon f for freight train distance f = df = 50 t p for passenger train dp = 60 (t-1) when is dp - df = 300 ? 60(t-1) - 50 t = 380 10 t - 60 = 380 10 t = 440 t = 44 hours so one day and 20 hours so 8 am --------------------------------- total distance = 2d ...
June 3, 2015

physics
120/360 = 1/3 of circumference so distance pushed = d = (1/3) 2 pi (.9) work = force * d = 11 *d Joules power = work/time = 11 * d / 2.2 in Watts
June 3, 2015

PHYSICS
v = a t where a = alpha = angular acceleration = torque/I here I is moment of inertia of uniform disc = (1/2) m r^2 so I = (1/2)(6)(.04) = .12 and a = 30/.12 = 250 radians/s^2 then v = 250 t and theta = (1/2)a t^2 = 4 pi radians so 125 t^2 = 4 pi t = .317 second then v = 250(....
June 3, 2015

math
3 x^2 - 12 x - 7 = 0 x = [ 12 +/- sqrt(144+84) ] / 6 = [ 12 +/- sqrt(228) ] / 6 = [ 12 +/- 2 sqrt(57) / 6 = [ 6 +/- sqrt(57) ] / 3 Use PARENTHESES !!!~!!~!!!!! I can not tell whsat is your numerator.
June 3, 2015

civics
Looks pretty federal to me.
June 3, 2015

civics
yes
June 3, 2015

civics
Well which do you think based on the answer to your other question?
June 3, 2015

math
0 = 1^2 - 1 3 = 2^2 - 1 8 = 3^2 - 1 15= 4^2 - 1 25= 5^2 - 1 Term = n^2 - 1
June 3, 2015

Physics
As far as I know a right hand rule is a right hand rule.
June 3, 2015

physics
first get acceleration of the two masses a = F/m = (2*9.81)/(7) then: mg - T = m a 2*9.81 - T = 2 a T = 2 (9.81 - a)
June 3, 2015

Math
because if they were similar then if V to W is 5 and R to S is 10 then if similar W to X must be HALF of S to T It is not, it is sqrt 5 times I know which sides to compare because I drew a quick sketch of the two figures.
June 2, 2015

Math
V to W = sqrt (25+0) = 5 R to S = sqrt (100+0) = 10 W to X =sqrt(49+9) = sqrt(58) S to T = sqrt(169+121) = sqrt (5*58) oh my :(, not twice, would be sqrt 4*58 if similar
June 2, 2015

Math
agree
June 2, 2015

physics
m g /area m = .050 KG g = 9.8 m/s^2 area = pi r^2 = pi (9 *10^-6) meters^2 so p = .0173 * 10^6 N/m^2 or Pascals = 1.73 * 10^4 Pascals or around .2 atmospheres
June 2, 2015

physics
That makes no sense to me at all. The total mechanical energy is the sum of the kinetic and potential energies.
June 2, 2015

Algebra
t = k/r 12 = k/60 so k = 12*60 then t = 12*60/85 = 8.47
June 2, 2015

Physics
well, the second equation is -A cos 41.9 + B cos 25.2 = 0 which is B = A(cos 41.9 / cos 25.2) so use that for B in the first equation
June 2, 2015

Physics
assume if A is in Quadrant 2 then B is in quadrant 1 (or the opposite, does not matter) sum of y components = 0 A sin 41.9 + B sin 25.2 - 25.8 = 0 sum of x components = 0 -A cos 41.9 + B cos 25.2 = 0
June 2, 2015

physics
d = .8 meter so F = G *55*70 /(.64) where G = 6.67*10^-11 m^3 /(kg s^2)
June 2, 2015

physics
force = 2*9.81 - 7 = 12.6 Newtons accelerated mass = 5 + 2 = 7 a = F/m = (12.6/7) m/s^2
June 2, 2015

Math
well, look at what happens to point (-1,0) it remains at (-1,0) when reflected around y=x+1 because it is on that line so just reflect it about y = x+3 drawing the graph I see it went left 2 from -1 and up the same amount, 2, from 0 so left 2 and up 2 :)
June 2, 2015

Math help please
40/80 = .5 20/80 = .25 60/80 = .75 so steepest 3/4 D
June 2, 2015

Math
believe me, it is much less confusing using another symbol for x^2 then replacing it at the end.
June 2, 2015

Math
let f(x) = z = x^2 so x = sqrt z and z always positive y = 3 (-4 sqrt z-2)^2 + 5 y = 3(16 z + 16 sqrt z +4) + 5 y = 48 z + 48 z^.5+ 17 y = 48 f(x) +48 f(x)^.5 + 17
June 2, 2015

Math
Steve and I both said the same thing in different ways. Here is another. like when is 2x+3 = 0 ??? when x = -3/2 so what is f(0) it is 0 so when x = -3/2 then g(x) = 0
June 2, 2015

Math
if x = -1, 2x+3 = 1 and -f(1) = -4 if x = 0, 2x+3 = 3 and -f(3) = -10 etc
June 2, 2015

Math
Huh? If that is a table of values of x and y, then y = 5 when x = 3
June 2, 2015

Physics
I guess you mean g = 10 m/s^2 Work done = increase in potential = m g * increase in height = 5 kg * 10 m/s^2 * 10 m = 500 Newton meters = 500 Joules
June 2, 2015

Math (check answers)
5 d^(6-12) = 5 d^-6 yes
June 1, 2015

civics
I think D is the correct answer. but knowing the speaker, it might be C :)
June 1, 2015

algebra--1 question
No, read above, a
May 31, 2015

algebra--1 question
check 14*75 = 1050 300 + 750 = 1050 sure enough
May 31, 2015

algebra--1 question
x^3+0x^2-7x+6/(x+3) = x^2-3x+2 which is a
May 31, 2015

Algebra II
agree but check as follows 1 + 5 (6-8) = 2 - (6+5) ???? 1 - 10 = 2 - 11 ??? -9 = - 9 Yes :)
May 31, 2015

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