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Exponents/288610: I have a question about the remaining factors.
If you have an equation of x^3+5x^2=2x-8 how do you find the remaining factors, if you know that one factor of the equation is (x+4)?
I tried out some problems, and figured out the remaining factors should be either (x+1),(x-2) or the remaining factors should be: (x-1),(x+2)........or am I wrong completely wrong?
And, could you please show me the way on HOW to figure this out? Thank you
1 solutions

Answer 209176 by richwmiller(9135) About Me  on 2010-04-05 08:27:26 (Show Source):
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The equation that you gave us x^3+5x^2=2x-8 does not have (x+4) as a factor.
I suspect you copied something wrong.
My best guess is that it isn't an equation at all and the = should be +
So here it is
(x^3+5x^2+2x-8)/(x+4)=
x^2+x-2=
(x-1)*(x+2)


Word_Problems_With_Coins/288601: Danial has 19 coins in dimes and nickels . after spending 85 cents , he has 5 dimes and 2 nickles left . how many nickels did Daniel have to start with ?
A 2 b 19 c 7 d 9 e 17

1 solutions

Answer 209174 by richwmiller(9135) About Me  on 2010-04-05 08:17:11 (Show Source):
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d+n=19
5*10+2*5=60 cents
60+85=145
10d+5n=145
d+n=19
d=10 n=9
check
10-5=5*10
9-2=7*5
5*10+7*5=85
Answer d)9


Linear-equations/288598: Given that the graph of the equation y = 2x+7/square root of 9-4x²,intersects the x axis once, how do I calculate the coordinates of this point of intersection

1 solutions

Answer 209173 by richwmiller(9135) About Me  on 2010-04-05 08:10:47 (Show Source):
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Intersecting the x axis means y is zero
set your equation to y=0 and solve for x.
Is this the problem?

y=%282x%2B7%29%2F%28sqrt%289-4x%5E2%29%29
x=-7/2
0+=+%282+x%29%2Fsqrt%289-4+x%5E2%29%2B7%2Fsqrt%289-4+x%5E2%29
2x+7=0
2x=-7
x=-7/2


Miscellaneous_Word_Problems/288602: Two adults and three children with a canoe on moose island want to go to Canary island.The canoe can hold either one adult and one child or three children. how many trips does the canoe have to make from one island to the other to ferry everyone across ?
A 2 b 3 c 4 d 5 e 6

1 solutions

Answer 209171 by richwmiller(9135) About Me  on 2010-04-05 07:59:15 (Show Source):
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Can't be done without sending at least 1 child on a return trip.
We don't know the ages of the children.
Are any of them able to paddle?
If we are magically returning the canoe then three trips
a+c
a+c
a+c
I don't like this problem


Probability-and-statistics/288489: A couple plan to have 4 children List the sample space assuming the outcome are equally likely
1 solutions

Answer 209106 by richwmiller(9135) About Me  on 2010-04-04 20:45:09 (Show Source):
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and what do you consider the equally likely outcomes?
They will; they won't.
Boy; girl
adoption? divorce?
death?


percentage/288482: what is the percent of the first ten letters of the alphabet are vowels
1 solutions

Answer 209104 by richwmiller(9135) About Me  on 2010-04-04 20:35:00 (Show Source):
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a,e and i
(3/10)*100=30%


Coordinate-system/288465: In the following exercise, find the coordinate of the vertex for the parabola defined by the given quadratic function.
f(x)=4^2-16x+8
The vertex is
1 solutions

Answer 209101 by richwmiller(9135) About Me  on 2010-04-04 20:14:33 (Show Source):
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The key to this problem is how do you find the vertex of a parabola.
What is the formula?


Quadratic_Equations/288466: Consider the quadratic equation, +y+=+x%5E2+
Which of the following statements is true?
A y is a function of x but x is not a function of y
B y is a function of x and x is a function of y
C y is not a function of x and x is not a function of y
D y is not a function of x but x is a function of y
I pretty much crossed out c and d because I'm pretty sure y IS a function of x... but I'm not sure if x is a function of y.
Thankyou! (:
1 solutions

Answer 209099 by richwmiller(9135) About Me  on 2010-04-04 20:12:33 (Show Source):
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The key to this is the definition of function.
google "math function"


Linear-equations/288474: how would you find the equation of a line if you were given the slope and x-intercept?
1 solutions

Answer 209098 by richwmiller(9135) About Me  on 2010-04-04 20:09:39 (Show Source):
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It would have been easier to explain with a real problem.


Polynomials-and-rational-expressions/288457: f(x)= -(x+8)^2-3
I need to find the vertex
line of symmetry is x=
the maximum/minimum value of f(x)is
the value f(-8)=-3is minumum or maximum.
1 solutions

Answer 209095 by richwmiller(9135) About Me  on 2010-04-04 19:39:04 (Show Source):
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What is the equation in standard form?
How do you find the vertex?
How do you find the line of symmetry?
How do you find the max/min? and how do you know which it is?
Show that you are willing to learn not just copy answers.


Surface-area/288462: the surface area s of the right circular cone is given by S=pi*r(r^2+h^2)square root. what radius should be used to produce a cone of height 5 inches and surface area 100 squared inches?
Dear tutors please your show work and thank you for your help.
1 solutions

Answer 209094 by richwmiller(9135) About Me  on 2010-04-04 19:33:19 (Show Source):
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Dear students,
Please show your work. Any work at all! Didn't do any. Didn't think so.


Linear-systems/288460: This needs to have the five step deal D, V, P, E, S. Thanks
Lauren Morse, a mathematics textbook editor, works 7.5 hr day. She spent a resent day making telephone calls, writing e-mails, and attending meetings. She spent twice as much time attending meetings as making telephone calls and .5 hr longer writing e-mails than making telephone calls.How many hours did she spend on each task?
1 solutions

Answer 209093 by richwmiller(9135) About Me  on 2010-04-04 19:30:28 (Show Source):
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I know Lauren. She is very careful about the answers in the back of the book.
t+m+g=7.5
g=2t
m=t+.5
g=3.5, m=2.25, t=1.75
t phone calls
m emails
g meetings


Travel_Word_Problems/288456: If it takes 3 hours to travel 24 miles downstream and 6 hours to travel upstream, how fast is the current if the speed of the boat remains constant?
A 1 mph
B 2 mph
C 3 mph
D 4 mph
thankyou.
1 solutions

Answer 209091 by richwmiller(9135) About Me  on 2010-04-04 19:23:24 (Show Source):
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3(b+c)=24
6(b-c)=24
b+c=8
b-c=4
2b=12
b=6
c=2
current is 2 mph



Linear-systems/288451: The revenue (in millions of dollars) from the sale of x units at a home supply outlet is given by R(x)=0.18x. The profit (in millions of dollars) from the sale of x units is given by P(x)=0.083x-1.1. Find the cost equation. What is the break-even point.
9. Cost equation
10. Break-even point

I think it is a trick question - I don't think there is a break-even point!
1 solutions

Answer 209088 by richwmiller(9135) About Me  on 2010-04-04 19:19:23 (Show Source):
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So where is your work?
Where is your cost equation?
What have you tried to find the break even point.
What is a break even point?
How can there not be a break even point?
If there is profit, there must be a break even point- just before profit begins.
We are given equations for revenue and profit but not for cost.
We have to equate cost and revenue for break even. We don't have the cost equation. That is the first thing to write.
profit minus revenue is cost.


Coordinate-system/288447: For the given circle, find the x-intercepts and the y-intercepts.
x^2+y^2-10x+4y+13=0
This is what I have so far:
To find the x-intercepts let y=0
X^2-10x+13=0
(x+___)(x-___) but this equation doesn't factor into integers as 13 is a prime number

1 solutions

Answer 209084 by richwmiller(9135) About Me  on 2010-04-04 19:01:44 (Show Source):
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This circle crosses the x axis twice but never crosses the y axis at all.
You have to complete the square twice to find the center and radius. The y intercepts are not integers either.
The center is at integer points and the radius is an integer.
But the problem doesn't ask for those.


Polynomials-and-rational-expressions/288435: the question is find the quotient using long division
the problem is 3x^3+2x^2-19x+1
--------------
x-2
i tried working the problem and i keep getting the answer 4x+6+29
---
x-4
1 solutions

Answer 209082 by richwmiller(9135) About Me  on 2010-04-04 18:49:58 (Show Source):
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So why do you think 4x+6 +29/(x-4) is wrong, if you got it twice?
It is obviously wrong since there is no x^2 term. The remainder is over (x-4) but you were dividing by (x-2)
and (x-4) into 3x^3 will obviously start out 3x^2
I suspect that you are scamming us. That you didn't even try.


Geometry_Word_Problems/288428: the sides of a parallelogram have lengths of 12 cm and 15 cm. find the lengths of the sides of a similar parallelogram with a perimeter of 90 cm.
1 solutions

Answer 209075 by richwmiller(9135) About Me  on 2010-04-04 18:29:51 (Show Source):
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2*12+2*15=24+30=54
24/54=2x/90
30/54=2y/90
2x=40
2y=50
x=20 y=25


Linear-systems/288427: U.S five cent coins are made from a combination of two metals.Nickel and copper. For every pound of nickel, 3 lbs of copper are used. How many pounds of copper would be needed to make 560 lbs of five cent coins?
1 solutions

Answer 209073 by richwmiller(9135) About Me  on 2010-04-04 18:22:20 (Show Source):
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3/4*560=3/4*140*4=3*140=420


Linear-systems/288424: the morena family drove to yoesmite national park in 3 hours 24 minutes. on the way home, they averaged5 miles per hour less and the trip took 3 hours 42 min. how far from yosemite national park do they live?
1 solutions

Answer 209071 by richwmiller(9135) About Me  on 2010-04-04 18:18:53 (Show Source):
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24/60==4/10=.4
42/60=7/10=.7
3.4x=3.7*(x-5)
x=61 2/3
x+5=66 2/3
3.4*61 2/3
209 2/3 miles


Linear-systems/288418: on a standardized test, correct answers are worth 2 points and incorrect answers are worth -1/4 point. alexandra wants to score at least 90 points on the test. if there are 50 questions on the test, what is the greatest number of questions she can miss
1 solutions

Answer 209067 by richwmiller(9135) About Me  on 2010-04-04 17:56:00 (Show Source):
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x+y=50
2x-y/4=90
y=40/9
y=4 +
so y=4
max that can be missed is 4
If she misses 4 she loses 1 point and doesn't get 8
So she gets 91
check
46*2=92
92-1=91


Polynomials-and-rational-expressions/288419: x² +7x+10 find the greatest common factor (polynomial)
1 solutions

Answer 209064 by richwmiller(9135) About Me  on 2010-04-04 17:35:52 (Show Source):


Linear-systems/288394: natalie spent $135 on new shorts and tops. the shorts were 15% off and the tops were 20% off. if she saved a total of $24, how much did she spend on tops
1 solutions

Answer 209063 by richwmiller(9135) About Me  on 2010-04-04 17:35:02 (Show Source):
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s= cost of shorts
t= cost of tops
.85s+.80t=135
.15s+.20t=24
s=156 t=3
156 original total on shorts
3 original total on tops
.85*156=132.60 discounted price on shorts
.80*3=4/5*3=12/5=$2.40 discounted price on tops
.15*156+.2*3=24
23.40+.60=$24.00
She spent $ 2.40 on tops
She spent $132.60 on shorts
Another way
.85s+.80t=135
.15s+.20t=24
.85s+.80t=135
.60s+.80t=96
subtract
.25s=39
25s=3900
s=3900/25
s=156
etc


Linear_Equations_And_Systems_Word_Problems/288381: You have $47 to spend at the music store. Each cassette tape costs $5 and each CD costs $10. Write and graph a linear inequality that represents this situation. Let x represent the number of tapes and y the number of CDs.
1 solutions

Answer 209049 by richwmiller(9135) About Me  on 2010-04-04 16:44:19 (Show Source):
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5x+10y<=47
the amount will never equal 47.
to graph just pick two values.
let x=0 and find y
let y=0 and find x


Geometry_Word_Problems/288387: One leg of a right triangle is 2 more than twice the smaller leg. If the hypotenuse is 1 inch more than the larger leg, find all 3 sides.
1 solutions

Answer 209048 by richwmiller(9135) About Me  on 2010-04-04 16:41:25 (Show Source):
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b=2+2a
c=1+b
a^2+b^2=c^2
this is a classic 5,12,13 right triangle
hypotenuse c=13


Linear-systems/288398: the veterinary clinic charges $5 to immunize dogs and $3 to immunize cats. a total of 45 dogs and cats were immunized, and $195 in fees were collected. how many dogs were collected.
1 solutions

Answer 209047 by richwmiller(9135) About Me  on 2010-04-04 16:37:45 (Show Source):
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d+c=45
5d+3c=195
no dogs were collected
fees were collected for immunizing the dogs and cats
fees for dogs =5d
solve for d and multiply by 5


Travel_Word_Problems/288395: 12. Trains A & B are traveling in the same direction on parallel tracks. Train A is traveling at 40 miles per hour and train B is traveling at 44 miles per hour. Train A passes a station at 5:15pm. If train B passes the same station at 5:45pm at what time will train B catch up to train A?
1 solutions

Answer 209046 by richwmiller(9135) About Me  on 2010-04-04 16:33:10 (Show Source):
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train a is going 40 mph for 30 minutes
so it goes 20 miles
train b is going 4 mph faster
so it will take 20/4=5 hours to catch up.
so at 10:45 pm train b will catch up to a
another way to do it
40*(t+1/2)=44t
40t+20=44t
20=4t
5=t
10:45 pm


Length-and-distance/288375: how to find distance from 3x+4y=1 to point (2,5) using graph paper? i know how to plot the equation and the distance is perpendicular segment form the equation and line i just want to know that how can i plot y-intercept when it is in fraction just like in this example the y-intercept is 1/4 . and if i plot it approximately then will it be correct answer ? please reply
1 solutions

Answer 209044 by richwmiller(9135) About Me  on 2010-04-04 16:27:34 (Show Source):
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you just discovered one of the biggest weaknesses of trying to solve equations by graphing. The results are not accurate.
Even if a point looks like it is a whole number it might not be.
And a point known to have fractions is even worse.


Exponential-and-logarithmic-functions/288389: (2/3)^1/8
1 solutions

Answer 209042 by richwmiller(9135) About Me  on 2010-04-04 16:16:55 (Show Source):
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(2/3)^1/8 means root%288%2C2%2F3%29
=.95058


Linear-systems/288393: your brother starts out 10 minutes before you on a bike path and rides at a rate of 9mph. if you ride at a rate of 12mph, how long will it take you to catch up to him
1 solutions

Answer 209041 by richwmiller(9135) About Me  on 2010-04-04 16:07:07 (Show Source):
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Brother got a 10 minute head start
In those ten minutes he went 9*1/6=9/6=1.5 miles
We are gaining on him at 3 mph.
So it will take 30 minutes to catch up
another way to do this
9*(x+1/6)=12*x
9x+1.5=12x
1.5=3x
1.5/3=x
1/2=x
x= 1/2 hr.


Functions/288299: The function A(t)=0.233t+5.87 can be used to estimate the median age of cars in the United States t years after 1990. (In this context, we mean that if the median age of cars is 3 yr, then half the cars are older than 3 yr and half are younger.)
a. Find the median age of cars in 2002.
b. In what year was the median age of cars 7.734 yr?

1 solutions

Answer 209028 by richwmiller(9135) About Me  on 2010-04-04 12:49:09 (Show Source):
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a) plug in 2002-1900 for t
b)plug in 7.734 for t and solve for A(t)
add that to 1990


Polynomials-and-rational-expressions/288351: Factor 50y^3+20y^2+2y
1 solutions

Answer 209025 by richwmiller(9135) About Me  on 2010-04-04 12:37:02 (Show Source):