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Madeline and Rufus are Chihuahuas and they are never indoors or outdoors at the same time; when one comes in, the other one goes out. Yesterday, Madeline spent 2/3 of the day indoors. How long did Rufus spend indoors? (Hint: they do this 24 hours a day, much to the dismay of their owners. 1 solutions
Answer 104524 by vleith(2825) on 2008-05-30 07:11:06 (Show Source):
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Linear-systems/143590: Solve system by the substitution method and indicate wheter each system is independent, inconsistent or dependent
x=1/8y-1
y=1/4x+39 1 solutions
Answer 104523 by vleith(2825) on 2008-05-30 07:08:58 (Show Source):
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Rectangles/143591: the lenght of a rectangle is 4 feet less than twice the width. the perimeter is 28 feet. find the length and width fo the rectangle. 1 solutions
Answer 104522 by vleith(2825) on 2008-05-30 07:03:26 (Show Source):
You can put this solution on YOUR website!Perimeter is the sum of all the sides.
Let w be the width.
L = 2w-4
P = w + l + w + l
28 = w + 2w -4 + w + 2w -4
28 = 6w - 8
36 = 6w
6 = w
l = 12 - 4
l = 8
Does that work?
28 = 12 + 16 check!
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Geometry_Word_Problems/143594: This question is from textbook Principles of Math
Two cabins, A and C are located 450m apart on the bank of a river. Across the river from the two cabins is a boathouse at B. Use the information in the diagram to calculate the width of the river. Angle CAB is 70 degrees. Angle BCA is 30 degrees.
1 solutions
Answer 104521 by vleith(2825) on 2008-05-30 06:59:37 (Show Source):
You can put this solution on YOUR website!See this --> http://en.wikipedia.org/wiki/Law_of_sines
Use the law of sines.
You are given 2 angles, so you can find the third angle (180 - (70+30) )
Now use law of sines to find the distance AB or AC
Once you have AB or AC, use sin and that length to find the width of the river.
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Permutations/143571: Please help me solve this extended word problem:
Given the following crcumstances tell if a combination or permutation and solve.
a. Cassandra has seven skirts, five blouses, and ten pair of shoes, how many outfits can she create? 1 solutions
Answer 104517 by vleith(2825) on 2008-05-30 04:51:36 (Show Source):
You can put this solution on YOUR website!Take a look at this video. There is a problem just voer halfway through that is almost exactly this problem.
http://collabvsl.wetpaint.com/page/Basic+Probability
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Geometry_Word_Problems/143596: This question is from textbook Principles of Math
A store sign is 9m high. The maximum length of the ladder is 10m Will the top of the ladder safely reach the sign? The ladder is 2m from the wall and the angle betweeen the ladder and the ground 75.5 degrees. Explain 1 solutions
Answer 104516 by vleith(2825) on 2008-05-30 04:48:02 (Show Source):
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Word_Problems_With_Coins/143545: Hi i have a question that is really baffaling me.Can someone please help me?
A jar of change has $90.15 in it.There are six less dimes than twice the nickels.There are three more quarters than 4 times the amount of nickels.How many nickels,dimes,and quarters are in the jar?(There are no pennies.)Thanks!! 1 solutions
Answer 104464 by vleith(2825) on 2008-05-29 16:52:54 (Show Source):
You can put this solution on YOUR website!90.15
Let n be the number of nickels
Dimes = 2n - 6 --> d = 2n - 6
Quarters = 4n + 3 --> q = 4n +3
9015 = 5n + 10d + 25q = n + 10*(2n - 6) + 25*(4n +3)
9015 = 5n + 20n - 60 + 100n + 75
9015 = 125n - 15
9000 = 125n
72 = n
d = 144 -6 = 138
q = 291
Does that check?
0.25*291 + 0.1*138 + 0.05* 72 = 90.15
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Linear-systems/143506: Oh, please help me with this, I do NOT understand this system math....
Solve the following system by substitution.
4x - 2y = 8
2x + 4y =8
1 solutions
Answer 104436 by vleith(2825) on 2008-05-29 10:58:42 (Show Source):
You can put this solution on YOUR website!see this --> http://collabvsl.wetpaint.com/page/Solving+Systems+of+Equations
4x - 2y = 8
2x + 4y =8
2x + 4y = 8
2x = 8 -4y
x = (8-4y)/2 use this and sub into the first equation
4x - 2y = 8
4((8-4y)/2) - 2y = 8
16 - 8y - 2y = 8
-10y = -8
y = 4/5
Use this value of y to sub back in and solve for x
x = 12/5
check your answers
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absolute-value/143508: I am so confused about this question, I don't know where to start. This is how it was typed on the word document.
. Jack was able to travel 30 miles downstream in 2 hours. In returning upstream, it took 3 hours to make the trip. How fast can his boat travel in still water? What was the rate of the river current?
2(r+c)=30--->2r+2c=30-->6r+6c=90
3(r-c)=30---->3r-3c=30--> 6r+6c=60
1 solutions
Answer 104434 by vleith(2825) on 2008-05-29 10:52:57 (Show Source):
You can put this solution on YOUR website!Minor error is causing you grief
2(r+c)=30--->2r+2c=30-->6r+6c=90
3(r-c)=30---->3r-3c=30--> 6r+6c=60 <-- you changed - to + here
3(r-c)=30---->3r-3c=30--> 6r-6c=60 should be this
Now just use elimination to solve. See here for a video on solving systems of equations. http://collabvsl.wetpaint.com/page/Solving+Systems+of+Equations
6r + 6c = 90
6r - 6c = 60
------------
12r = 150
r = 12.5
r+c = 15
12.5 + c = 15
c = 2.5
Does that check out?
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Graphs/143482: how to draw graph for equation Y=6x3 1 solutions
Answer 104427 by vleith(2825) on 2008-05-29 07:28:35 (Show Source):
You can put this solution on YOUR website!There is really no simple way to do that beyond taking a few points and making a table.
I suggest plugging in x = -3, -2, -1, 0, 1, 2, 3 Solve for Y at each of those values of x. Then plot the points. The shape of the plot will be clear enough with that number of points.
X Y
-3 6*(-3)^3 = -162
-2 6*(-2)^3 = -48
-1 -6
0 0
1 6
2 48
3 162
Make sure your graph scale is large enough allow for the fact that the Y values are growing exponential.
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Geometry_Word_Problems/143495: a man stands atop a building. he measures the angle of elevation to the building across the street to be 20 degrees and the angle of depression(to the base of the building) to be 35 degrees. if two buildings are 50 feet apart how tall is the taller building. please show all work and find the solution 1 solutions
Answer 104425 by vleith(2825) on 2008-05-29 07:22:57 (Show Source):
You can put this solution on YOUR website!You have two right triangles.
Both have an adjacent leg of 50 ft.
Looking up at 20degrees. The opposite leg of the 'upper triangle' can be found by
Looking down at 35 degrees. The opposite leg of the lower triangle' can be found by
So the next building is  = 53.21ft high
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Rational-functions/143465: The view of rectangular box at the right shows three faces of the box. The areas of two of the faces are 30 cm squared and 48 cm squared. The volume of the box is 240 cm cubed. What is the area of the third face? 1 solutions
Answer 104419 by vleith(2825) on 2008-05-29 06:20:27 (Show Source):
You can put this solution on YOUR website!You are given three pieces of information.
Label the axis on the box w, d and h (for width, depth and height).
Now setup equations for what you 'know'
 -->
 -->
Combining the previous two equations yeilds
Now plug in the values for d and h into the Volume equation.

Reduce to get
Substitute w=5 back into the earlier equations to get
 = 6
 =  = 8
That's a pretty small box
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Length-and-distance/143487: A rectangular field is 260 feet in perimeter.the length is 10 feet more than twice the width.what is the length? 1 solutions
Answer 104418 by vleith(2825) on 2008-05-29 06:10:09 (Show Source):
You can put this solution on YOUR website!Let the width = w.
The length is given as "10 feet more than twice the width". So
The perimeter is givenb as 260 feet. You know the perimeter of a rectangle is
Check your answer.
If w = 40 , then length = 10+80 = 90.
Is 2*40 + 2+90 = 260??
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test/143488: 7y^2 divided by 2 X 8x divided by 20y 1 solutions
Answer 104417 by vleith(2825) on 2008-05-29 06:05:42 (Show Source):
You can put this solution on YOUR website!watch this - I bet you can do it yourself afterwards
http://collabvsl.wetpaint.com/page/Simplifying+rational+expressions+using+multiplication+or+division
Let me know if you can't get it after watching
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Radicals/143490: I wasnt sure how to insert a radicand, so I used/ to represent the radicand I need help with the problem, thank you in advance!
7/45-2/5
1 solutions
Answer 104415 by vleith(2825) on 2008-05-29 06:02:07 (Show Source):
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logarithm/143336: Use Logarithms to answer the following questions :
1) C = 3.8^2 / 0.943
2) B = cube root of (28.6/0.987)
3) A = (cube root of (39304))/ 136
4) A = square root of ( (16.843)^0 * cube root of(18.8) )
Please help, i need help with these to prepare for an exam.
Thanks
Rebekah 1 solutions
Answer 104305 by vleith(2825) on 2008-05-28 06:53:57 (Show Source):
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Trigonometry-basics/143235: I am completely confused regarding trig, the beginner trig in involving right triangles:
Sin: opposite leg/ hypotenuse
Cos: adjacent leg/ hypotenuse
Tan: adjacent leg/opposite leg
Is this correct?
How do you know what leg is adjacent?
What happens when you have a angle but you need to find a leg number? Do you use 'sin-1'? 1 solutions
Answer 104235 by vleith(2825) on 2008-05-27 16:00:38 (Show Source):
You can put this solution on YOUR website!Tangent = opposite/adjacent
See here for a good picture --> http://www.grc.nasa.gov/WWW/K-12/airplane/sincos.html
When thinking about sine, cosine and tangent, one has to think about which vertex of the triangle you are referencing. Assume you pick one vertex, then the adjacent leg is the one that 'touches' your vertex. The hypotenuse is always the 'long side'. make sense?
When you have an angle, and also one of the sides (but not a second side), you setup the ratios as you nothed above, and then use your calculator to find the sine or cosine ro tangent of the angle. The cross multiply to find the unknown side.
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Geometry_proofs/143178: parallelogram abcd is not a rectangle the points of a b c and d are (-2,2) (6,5) (4,0) (-4,-3) prove that paralleogram is not a rectangle 1 solutions
Answer 104230 by vleith(2825) on 2008-05-27 15:16:45 (Show Source):
You can put this solution on YOUR website!All you need to do is prove the line segments that create one of the vertex are not at right angles.
Find the slope of one side segment, then find the slope of the segment that intersects at that vertex. Then show the products of those slopes is not equal to -1.
If you can show that, then the shape cannot be a rectangle.
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Subset/143197: This question is from textbook Survey of Math w/ Apllications
Could you help me solve this px
6. (3 pts) Given U = {l, m, n, o, p, q, r, s, t, u, v, w}, A = {l, m, n, o, p, q}, B = {n, o, r, s, v, w}, and C = {l, m, p, q, r, t}, find (A′ U C′) ∩ B′. 1 solutions
Answer 104229 by vleith(2825) on 2008-05-27 15:12:23 (Show Source):
You can put this solution on YOUR website!A' is everything in U that is not in A --> A'={r,s,t,u,v,w}
C' is everything in U not in C --> C' = {n,o,s,u,v,w}
Union of A' and C' is everything in either one A' U C' ={n,o,r,s,t,u,v,w}
Now you figure out B'
Then take the intersection og B' and A' U C' (get the elements that are common to both B' and A'U C')
Ping me if you dont understand
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Square-cubic-other-roots/143203: 7times the square root of 7 mnus 2 times the squre root of 7 1 solutions
Answer 104228 by vleith(2825) on 2008-05-27 15:06:50 (Show Source):
You can put this solution on YOUR website!
Let sqrt(7) be x
Can you solve that one? i bet you can.

but x = sqrt(7)
The sqrt(7) adds and subtracts just like any other number ... just more difficult to get your mind around what the value is. For this problem, we don't care what the sqrt(7) is. We just let it ride !
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Money_Word_Problems/143231: Hi, another question from the GRE math test prep.
A group can charter a particular aircraft at a fixed total cost. If 36 people charter the aircraft rather than 40 people, then the cost per person is greater by $12. What is the cost per person if 40 people charter the aircraft?
Thank you!!
Lauren 1 solutions
Answer 104226 by vleith(2825) on 2008-05-27 14:55:51 (Show Source):
You can put this solution on YOUR website!let the total cost = C
The person cost is :
Let the cost per person with 40 = c
The cost per person at 36 = c+ 12
Total cost is the same:
Check yor answer. does 40*108 = 36(120)?? as they say in fargo 'you betcha'
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logarithm/143204: 3^x=40
e^0.04t=1500
please help me solve these... if possible...i need good step by step process
1 solutions
Answer 104225 by vleith(2825) on 2008-05-27 14:46:26 (Show Source):
You can put this solution on YOUR website!Use logs
Given: 
Take the log of both sides

When using logs, if the term inside parens is raised to a power, then your can 'bring the power down' as a multiplier.

Now get out your handy calculator and find log(3) and log(40)

Now solve for x as a one step algebra simplification
Finally, check your answer using a calculator. Does 3^3.3576 = 40? Close enough!
For the second problem, use logs again. Except this time, use natural log (ln)
Given: 
Take the ln of both sides

The ln of a power of e, it just the power.

Whip out your calculator and find ln(1500) (somebody help that man!)
Check your answer using the calculator. Does it check out? You bet it does,
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