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27270..27299 , 27300..27329 , 27330..27359 , 27360..27389 , 27390..27419 , 27420..27449 , 27450..27479 , 27480..27509 , 27510..27539 , 27540..27569 , 27570..27599 , 27600..27629 , 27630..27659 , 27660..27689 , 27690..27719 , 27720..27749 , 27750..27779 , 27780..27809 , 27810..27839 , 27840..27869 , 27870..27899 , 27900..27929 , 27930..27959 , 27960..27989 , 27990..28019 , 28020..28049 , 28050..28079 , 28080..28109 , 28110..28139 , 28140..28169 , 28170..28199 , 28200..28229 , 28230..28259 , 28260..28289 , 28290..28319 , 28320..28349 , 28350..28379 , 28380..28409 , 28410..28439 , 28440..28469 , 28470..28499 , 28500..28529, >>NextMoney_Word_Problems/195126: i have the first part of this question solved, i just need help with the second part. thank you.
a company earns a weekly profit of P=-1.2x^2+180x-280, where x is the number of coffee tables they build and sell and P is profit in dollars.
a. find the number of coffee tables the company must sell in a week in order to obtain max. profit.
(i completed the work for this problem and got 75 coffee tables)
b. what is the maximum profit?
(i have the answer key and i tried plugging 75 coffee tables into the equation but i am getting an answer that seems to be way off)
thank you for your help 1 solutions
Answer 146355 by jim_thompson5910(28536) on 2009-05-06 16:15:26 (Show Source):
You can put this solution on YOUR website!a) Correct.
b)
 Start with the given equation.
 Plug in  .
 Square  to get  .
 Multiply  and  to get  .
 Multiply  and  to get  .
 Combine like terms.
So the max profit is $6,470.
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Linear-systems/195096: This question is from textbook algebra 1 concepts and skills
3x-2y=11
-x+6y=7
(5,2) 1 solutions
Answer 146336 by jim_thompson5910(28536) on 2009-05-06 13:37:28 (Show Source):
You can put this solution on YOUR website!
Let's see if  and  are solutions to the first equation.
 Start with the first equation.
 Plug in  and  .
 Multiply
 Combine like terms.
Since the equation is true, this means that (5,2) is a solution to the first equation.
Let's see if (5,2) is a solution to the second equation.
 Start with the second equation.
 Plug in  and  .
 Multiply
 Combine like terms.
Since the equation is true, this means that (5,2) is also a solution to the second equation.
Since all of the equations of the system are true, this means that (5,2) is a solution to the given system.
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Signed-numbers/195102: I have another two questions. This is confusing to me too. please help me.
3.) What value should be added to the expression to create a perfect square?
x2 - 20x
4. Solve.
x2 + 8x 8 = 0
1 solutions
Answer 146334 by jim_thompson5910(28536) on 2009-05-06 13:32:58 (Show Source):
You can put this solution on YOUR website!3)
 Start with the given expression
Now take half of the x coefficient and square it to get  . This is the value that you add to the expression to make it a perfect square.
So  is a perfect square.
4)
Is the equation  ???
 Start with the given equation.
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Square  to get  .
 Multiply  to get
 Subtract  from  to get
 Multiply  and  to get  .
 Simplify the square root
 Break up the fraction.
 Reduce.
 or  Break up the expression.
So the answers are  or
which approximate to  or
------------------------------------------------------
OR....
Is the equation  ???
 Start with the given equation.
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Square  to get  .
 Multiply  to get
 Rewrite  as
 Add  to  to get
 Multiply  and  to get  .
 Simplify the square root
 Break up the fraction.
 Reduce.
 or  Break up the expression.
So the answers are  or
which approximate to  or
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Complex_Numbers/195104: Simplify quotient and write answer in a + bi form.
6 + 2i divided by 4-3i 1 solutions
Answer 146328 by jim_thompson5910(28536) on 2009-05-06 12:58:59 (Show Source):
You can put this solution on YOUR website! Start with the given expression.
 Multiply the fraction by  .
 Combine the fractions.
 FOIL the numerator.
 FOIL the denominator.
 Multiply.
 Combine like terms.
 Break up the fraction.
So  .
So the expression is now in standard form  where  and
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Quadratic_Equations/194983: Solve 6x^2+38x+12=0 1 solutions
Answer 146261 by jim_thompson5910(28536) on 2009-05-05 19:43:02 (Show Source):
You can put this solution on YOUR website!
 Start with the given equation.
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Square  to get  .
 Multiply  to get
 Subtract  from  to get
 Multiply  and  to get  .
 Take the square root of  to get  .
 or  Break up the expression.
 or  Combine like terms.
 or  Simplify.
So the answers are  or
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Polynomials-and-rational-expressions/194980: I need help with this factoring problem if you could?????
4s^3+s^6-45=
Thanks for all your help!!!!! 1 solutions
Answer 146259 by jim_thompson5910(28536) on 2009-05-05 19:40:36 (Show Source):
You can put this solution on YOUR website! Start with the given expression.
 Rearrange the terms.
Looking at  we can see that the first term is  and the last term is  where the coefficients are 1 and -45 respectively.
Now multiply the first coefficient 1 and the last coefficient -45 to get -45. Now what two numbers multiply to -45 and add to the middle coefficient 4? Let's list all of the factors of -45:
Factors of -45:
1,3,5,9,15,45
-1,-3,-5,-9,-15,-45 ...List the negative factors as well. This will allow us to find all possible combinations
These factors pair up and multiply to -45
(1)*(-45)
(3)*(-15)
(5)*(-9)
(-1)*(45)
(-3)*(15)
(-5)*(9)
note: remember, the product of a negative and a positive number is a negative number
Now which of these pairs add to 4? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 4
| First Number | Second Number | Sum | | 1 | -45 | 1+(-45)=-44 | | 3 | -15 | 3+(-15)=-12 | | 5 | -9 | 5+(-9)=-4 | | -1 | 45 | -1+45=44 | | -3 | 15 | -3+15=12 | | -5 | 9 | -5+9=4 |
From this list we can see that -5 and 9 add up to 4 and multiply to -45
Now looking at the expression  , replace  with  (notice  adds up to  . So it is equivalent to  )
Now let's factor  by grouping:
 Group like terms
 Factor out the GCF of  out of the first group. Factor out the GCF of  out of the second group
 Since we have a common term of  , we can combine like terms
So  factors to
So this also means that  factors to  (since  is equivalent to  )
------------------------------------------------------------
Answer:
So  completely factors to
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Polynomials-and-rational-expressions/194979: Hi, could you please help me with factoring?
4s^3+12s^2-64s-192=
I am not sure what I am doing, but I am not coming up with the correct answer.
Thanks 1 solutions
Answer 146258 by jim_thompson5910(28536) on 2009-05-05 19:38:15 (Show Source):
You can put this solution on YOUR website! Start with the given expression
 Factor out the GCF
 Group like terms
 Factor out the GCF  out of the first group. Factor out the GCF  out of the second group
 Since we have the common term  , we can combine like terms
 Factor  to get
So  completely factors to
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Trigonometry-basics/194974: How do you verify cos(A+B)+cos(A-B)=2cosAcosB 1 solutions
Answer 146251 by jim_thompson5910(28536) on 2009-05-05 19:05:33 (Show Source):
You can put this solution on YOUR website!I'd start with the left side and work my way to get it equal to the right side (if you go with the left side, do NOT change the right).
Recall the identities:
cos(A+B) = cos(A)cos(B)-sin(A)sin(B), and
cos(A-B) = cos(A)cos(B)+sin(A)sin(B)
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cos(A+B)+cos(A-B)=2cos(A)cos(B) ... Start with the given equation.
[cos(A)cos(B)-sin(A)sin(B)]+cos(A-B)=2cos(A)cos(B) ... Use the first identity given above
[cos(A)cos(B)-sin(A)sin(B)]+[cos(A)cos(B)+sin(A)sin(B)]=2cos(A)cos(B) ... Use the second identity given above
[cos(A)cos(B)+cos(A)cos(B)]+[-sin(A)sin(B)+sin(A)sin(B)]=2cos(A)cos(B) ... Rearrange the terms.
2cos(A)cos(B)+0=2cos(A)cos(B) ... Combine like terms.
2cos(A)cos(B)=2cos(A)cos(B) ... Simplify
Since both sides are equal, we've verified the identity.
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Complex_Numbers/194943: please explain how to simplify...
i to the 100th power 1 solutions
Answer 146249 by jim_thompson5910(28536) on 2009-05-05 18:56:12 (Show Source):
You can put this solution on YOUR website!Since  , this means that
 or
 or
 or
 or
etc...
----------------------------------
So for every increment of the exponent, the powers of "i" are: i, -1, -i, 1, i, etc... and this pattern repeats every 4 terms (notice how the 5th term is identical to the first term).
This pattern can be generalized to the following:
For  (where "k" is a whole number),
If the remainder of  is 0, then  .
If the remainder of  is 1, then  .
If the remainder of  is 2, then  .
If the remainder of  is 3, then  .
So out at the 100th term, since  remainder 0, this means that
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Equations/194965: x/4 + 11x/4 = x/20 1 solutions
Answer 146243 by jim_thompson5910(28536) on 2009-05-05 18:37:59 (Show Source):
You can put this solution on YOUR website! Start with the given equation.
 Multiply EVERY term by the LCD  to clear any fractions.
 Multiply.
 Combine like terms on the left side.
 Subtract  from both sides.
 Combine like terms on the left side.
 Divide both sides by  to isolate  .
 Reduce.
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Answer:
So the answer is
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Expressions-with-variables/194899: I'm very confused about this problem, so I really hope someone can help me. I dont know how to type this and I looked at the fourmula plotting system but couldnt find anything, so I will try to explain it the best I can.
I have to write an expression for the following.
y+y+...+y
(then there is a curly bracket under it making it look like a fraction(except that its a curly bracket) and under the bracket is the following)
x of them 1 solutions
Answer 146237 by jim_thompson5910(28536) on 2009-05-05 18:31:35 (Show Source):
You can put this solution on YOUR website!Let's start off with some simple cases:
Case 1: If we have only one y, then we'll simply have
Case 2: If we add up two y's, then
Case 3: If we add up three y's, then
Case 4: If we add up four y's, then
etc...
So all we're doing is placing the number of y's that we're adding in front of the y's.
So if we add up 5 y's, then we'll get
If we add up 22 y's, then we'll get  .
So if we add up "x" y's, then we'll get  which is the answer.
Note: the reason why this works is because multiplication is really a shortcut for repeated addition.
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Probability-and-statistics/194866: 1 solutions
Answer 146186 by jim_thompson5910(28536) on 2009-05-05 12:02:09 (Show Source):
You can put this solution on YOUR website!# 1
Remember, probability is simply a formal way of representing the chance of an event occurring. Probability is most often represented as a fraction where the numerator is the number of ways that given event can occur over the denominator which represents the total number of possible outcomes.
In other words, this fraction looks like
where the notation "P(Event Occurring)" stands for "the probability of the event occurring"
So whenever you hear something like "the chances of that happening are one out of two", they mean that the event can occur one way out of two possible ways total. So they might be describing a coin toss where the chances of heads is "one out of two" since there's only one way to land on heads out of the two possible sides of the coin.
a)
Let's say that we have a deck of 52 cards and I want to know what the chances are of drawing a blue card. Since there are NO blue cards (there are only red and black cards), this means that the numerator is equal to zero while the denominator is still equal to 52. So this means that the probability of drawing a blue card is:
So the probability of choosing a blue card is 0 which means that there's a 0% chance of choosing a blue card.
----------------------
b)
Let's again say that we have a deck of 52 cards, but this time we want to know the chances of drawing a card (this is trivial, but important). Since there are 52 cards, and there are 52 ways to draw one card, this means that
So the probability of drawing a card is 1. In other words, no matter which card you choose, you're still selecting a card. So there is a 100% certainty that you'll select a card.
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# 2
The outcomes of an experiment are the results after running the simulation. Whatever experiment you run, the outcomes are the OBSERVED occurrences of an event.
For instance, let's say that you're flipping a coin and you observe the coin lands on: heads, tails, heads, heads, heads, and tails.
The outcomes of the experiment are the results of heads, tails, heads, heads, heads, and tails where the experiment is flipping a coin.
Note: an experiment in this sense is simply a simulation of an event (eg flipping a coin, rolling a die, drawing a card)
-----------------------------------------
Here's another example. Now you're rolling a single die and you roll the following: 1, 4, 2, 5, 1, 6, 2, and 3
The numbers 1, 4, 2, 5, 1, 6, 2, and 3 are all outcomes of the experiment of rolling a die.
Note: A more sophisticated experiment would involve more factors (and not be as simple as rolling a die or flipping a coin).
-----------------------------------------
When we say that the outcomes are equally likely, we're simply saying that the probability of the outcomes are equal.
Back in the coin flipping example, the chances of landing on heads is  (since there's one way to get heads out of 2 possible outcomes). Likewise, the chances of getting tails is also  (there's one way to get tails out of 2 possible outcomes).
Since  , this means that the chances of getting either one is equally likely. So this means that the outcomes are equally likely.
In the die rolling example, the chances of rolling any number from 1 to 6 are  (since for any given number, there's only one way to get that number out of the 6 numbers on the die). Since the chances of getting any number on the die is  , these outcomes are also equally likely.
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Quadratic_Equations/194753: Please Help. Use the discriminant to determine the number types of solutions of the quadratic equation t^2+8t+20=0. 1 solutions
Answer 146100 by jim_thompson5910(28536) on 2009-05-04 19:44:20 (Show Source):
You can put this solution on YOUR website!
From  we can see that  ,  , and
 Start with the discriminant formula.
 Plug in  ,  , and
 Square  to get
 Multiply  to get
 Subtract  from  to get
Since the discriminant is less than zero, this means that there are two complex solutions.
In other words, there are no real solutions.
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Travel_Word_Problems/194738: The rate of a jet is 400 mph in calm air. Traveling with the wind, the jet can fly 2100 miles in the same amount of time as it takes to fly 1900 miles against the wind. Find the rate of the wind.
d=rt
calm air = 400 mph
distance with wind = 2100 miles
distance against wind = 1900 miles
2100 = (400+w)*?
1900 = (400-w)*?
I understand that we need to find w(rate of wind), but what's the time? The problem just states that it is the same. 1 solutions
Answer 146091 by jim_thompson5910(28536) on 2009-05-04 18:49:13 (Show Source):
You can put this solution on YOUR website!Since the times are the same, the time is simply "t" for both equations.
So we have the equations
 Start with the first equation.
 Divide both sides by  .
 Rearrange the equation
------------------------
 Move onto the second equation
 Plug in
 Multiply both sides by  .
 Rearrange the terms.
 Distribute.
 Subtract  from both sides.
 Add  to both sides.
 Combine like terms on the left side.
 Combine like terms on the right side.
 Divide both sides by  to isolate  .
 Reduce.
So the speed of the wind is 20 mph.
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Complex_Numbers/194674: This question is from textbook An Introduction to Abstract Algebra with Notes to the Future Teacher
with the help of the quadratic formula, find all the complex roots of each of the polynomials given in exercise 1.
iii) z^3 + i 1 solutions
Answer 146065 by jim_thompson5910(28536) on 2009-05-04 15:57:40 (Show Source):
You can put this solution on YOUR website!First, perform synthetic division on the polynomial  using the test zero  . Note: you can easily solve for "z" and find that one solution is
i | 1 0 0 i
| i -1 -i
-----------
1 i -1 0
Since the first three numbers in the third row are 1, i, and -1, this means that
Now simply use the quadratic formula to solve  for "z":
 Start with the quadratic formula
 Plug in  ,  , and
 Square  to get  .
 Multiply
 Combine like terms.
So the other two solutions are  or
===========================================================
Answer:
So the 3 solutions are  ,  , or
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Radicals/194682: This question is from textbook Florida Algebra 1
I need help with this problem: A rectangle is 7 times as long as it is wide. Its area is 1400cm^2. Find the dimensions of the rectangle in simplest radical form.
I have been working on this problem for 30 minutes straight, and I can't find the way to work it out. I tried to use this equaion to solve the problem (length=7w): 
I didn't work. Please help me. 1 solutions
Answer 146059 by jim_thompson5910(28536) on 2009-05-04 15:37:05 (Show Source):
You can put this solution on YOUR website!I'm not sure how you got what you have, but I think you're confusing the area and perimeter formulas.
Since "A rectangle is 7 times as long as it is wide", this means that  . Also, because "Its area is 1400cm^2", we know that
Recall, the area of a rectangle is
 Start with the area of a rectangle formula
 Plug in  and
 Multiply
 Divide both sides by 7
 Reduce
 Rearrange the equation
 Take the square root of both sides. Note: we're only considering the positive square root.
 Factor 200 to get 100*2
 Break up the square root.
 Take the square root of 100 to get 10
 Go back to the first equation
 Plug in
 Multiply
So the length is  cm and the width is  cm
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Radicals/194619: Hi! What is radical 3x+1=5 1 solutions
Answer 146007 by jim_thompson5910(28536) on 2009-05-04 11:36:04 (Show Source):
You can put this solution on YOUR website! Start with the given equation
 Square both sides
 Square 5 to get 25
 Subtract  from both sides.
 Combine like terms on the right side.
 Divide both sides by  to isolate  .
 Reduce.
----------------------------------------------------------------------
Answer:
So the solution is
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Graphs/194499: Please help me solve I'm having trouble with graphing y=-2/3x-12 I know how to point them on the graph but I'm having trouble solving the equation to determine if the point's (-4, 10) are correct. no text book 1 solutions
Answer 145935 by jim_thompson5910(28536) on 2009-05-03 19:30:31 (Show Source):
You can put this solution on YOUR website!
Looking at  we can see that the equation is in slope-intercept form  where the slope is  and the y-intercept is
Since  this tells us that the y-intercept is ) .Remember the y-intercept is the point where the graph intersects with the y-axis
So we have one point
Now since the slope is comprised of the "rise" over the "run" this means
Also, because the slope is  , this means:
which shows us that the rise is -2 and the run is 3. This means that to go from point to point, we can go down 2 and over 3
So starting at ) , go down 2 units
and to the right 3 units to get to the next point
Now draw a line through these points to graph
So this is the graph of  through the points ) and
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Radicals/194496: 5x squared + 2x - 3 = 0
I added 3 on both sides.
5x squared + 2x = 3
But i'm a bit lost.
Someone please help me. I'd provide you with a book but we don't use books in my math class. 1 solutions
Answer 145934 by jim_thompson5910(28536) on 2009-05-03 19:27:26 (Show Source):
You can put this solution on YOUR website!
 Start with the given equation.
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Square  to get  .
 Multiply  to get
 Rewrite  as
 Add  to  to get
 Multiply  and  to get  .
 Take the square root of  to get  .
 or  Break up the expression.
 or  Combine like terms.
 or  Simplify.
So the answers are  or
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Quadratic_Equations/194493: find the equation of a quadric function with x- intercepts (2,0) and (-7,0) and y intercept (0,5)
please i need help for this problem please i need help i have exam on Tuesday 05/07/09 so it is urgent!!!!! 1 solutions
Answer 145933 by jim_thompson5910(28536) on 2009-05-03 19:26:23 (Show Source):
You can put this solution on YOUR website!Since the equation has the x- intercepts (2,0) and (-7,0), this means that the roots are  or
 or  Start with the given roots.
 or  Get everything to the left side.
 Combine the equations using the zero product property. Also, insert the variable "a" (this will be used to make the graph have a y-intercept of (0,5))
 FOIL
So the general equation with the x- intercepts (2,0) and (-7,0) is:
 Start with the given equation.
 Distribute
 Plug in  and  (from the point (0,5))
 Multiply and simplify
 Divide both sides by -14.
 Reduce and rearrange the equation.
 Go back to the previous equation
 Plug in
 Multiply and simplify
So the quadratic equation is
Here's a graph to visually confirm the answer:
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Quadratic_Equations/194491: x squared - 10x + 9 = 0
I subtracted 9 on both sides.
x squared - 10x = -9
and I'm lost from here. Can someone please help me? 1 solutions
Answer 145931 by jim_thompson5910(28536) on 2009-05-03 19:14:34 (Show Source):
You can put this solution on YOUR website!Note: because this is a quadratic and there are two terms that involve "x", you can't isolate "x" using linear techniques.
 Start with the given equation.
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Negate  to get  .
 Square  to get  .
 Multiply  to get
 Subtract  from  to get
 Multiply  and  to get  .
 Take the square root of  to get  .
 or  Break up the expression.
 or  Combine like terms.
 or  Simplify.
So the answers are  or
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logarithm/194487: Explain how to get the graph of the function f(x)=e^(x-2)+3 from the graph of the function g(x)=e^x. 1 solutions
Answer 145926 by jim_thompson5910(28536) on 2009-05-03 18:50:26 (Show Source):
You can put this solution on YOUR website!Start with the graph of
Now shift the graph over 2 units to the right to graph
Graph of  (red) and  (green)
Finally, shift the previous graph up 3 units to get the graph of
Graph of  (red),  (green), and  (blue)
So the graph of  is
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Surface-area/194484: This question is from textbook
I am completely lost on solving this question. Please help.
Find the unknown length, width, or height of the rectangular prism.
V=120m^3, l=4m, w=_____, h=5m 1 solutions
Answer 145922 by jim_thompson5910(28536) on 2009-05-03 18:33:41 (Show Source):
You can put this solution on YOUR website! Start with the volume of a rectangular prism formula.
 Plug in the volume of  and the length and height of  and  . We'll use "x" for the unknown width.
 Multiply
 Divide both sides by 20 to isolate "x"
 Reduce
So the solution is  which means that the length is 6 meters.
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