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Graphs/213221: This question is from textbook algebra1
{(-2,-4),(-1,-1),(0,0)(1,-1),(2,-4)}
it ask to express each relation as a table, as a graph, and as a mapping diagram.
I don't know how to do that
like what exactly do you do 1 solutions
Answer 161080 by vleith(2825) on 2009-09-13 15:09:55 (Show Source):
You can put this solution on YOUR website!1)As a table, make a table with 2 columns and 5 rows. Label the first column "x" and the second column "y". Then use the coordinates of the given points to fill in the table.
row 1 has -2 -4
row 2 has -1 -1
and so on
2) As a graph, lay down a standard Cartesian grid (like graph paper). Then plot the 5 given points. If you see a "curve" in thyat data, then sketch in the curve
3) As mapping diagram, draw an ellipse shaped like a "0", leave an inch of two of space and then draw a second one to the right of the first (same shape, same size).
Put all of the x values in the left ellipse (see column one from the table in part 1). Put all the y values in the right ellipse (see column two from the table above).
Now connect the x values in the left ellipse with the corresponding y values in the roght ellipse. Just draw a line from one to the other. That is the "map"
See this URL for an example --> http://img.sparknotes.com/figures/4/4d7924c96427a340a0f1be4c7e650f7c/mapping.gif
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Functions/212978: given the function defined by y=-7x^2+3x-8
determine whether function opens upward or downward 1 solutions
Answer 160885 by vleith(2825) on 2009-09-12 13:14:20 (Show Source):
You can put this solution on YOUR website!downward, the high order coeefficient (-7 on the x^2 term) is negative. So it must open down.
See this URL for a plot --> http://www.wolframalpha.com/input/?i=-7x^2%2B3x-8
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Triangles/212968: The hypotenuse of a right triangle is twice as long as one of the legs and 4 inches longer than the other. What are the lengths of the sides of the triangle? 1 solutions
Answer 160883 by vleith(2825) on 2009-09-12 13:12:47 (Show Source):
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Graphs/212970: sketch the graph of the function
y= x^2+12y-36 1 solutions
Answer 160881 by vleith(2825) on 2009-09-12 13:04:18 (Show Source):
You can put this solution on YOUR website!

Pick some values for x, and then solve for y. Plot those points and draw the curve.
Use this URL to check your answer
http://www.wolframalpha.com/input/?i=(36-x^2)%2F11
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Expressions-with-variables/212860: How do I find the solution to this input output problem? E P
1 3
2 5
3 9
4 17
5 33 1 solutions
Answer 160840 by vleith(2825) on 2009-09-12 07:06:01 (Show Source):
You can put this solution on YOUR website!Most of these type problems are practice. I like to start by looking at the series of numbers. You can see the difference in the inputs goes up by 1 one each entry. Now look and see if you can find a pattern in the output numbers.
You can see they are getting larger by increasingly larger amounts. However, nothing obvious jumps out a bout their values. So, the first thing I like to try is to see if there are patterns in the series of outputs. For instance, perhaps every other number has an obvious pattern. One thing I always try is finding the difference between each successive output number.
difference between 5 and 3 = 2
difference between 9 and 5 = 4
difference between 17 and 9 = 8 do you see the pattern yet
difference between 33 and 17 = 16
So each output increases by a value that is power of 2. Now all that is left to figure out is what the 'starting' value is. A little trail and error will show you that value is 1.
So, the function that fits the given data points is
 x>=1
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Permutations/212781: How many different ways can 9 letters be grouped without any letter being repeated? 1 solutions
Answer 160711 by vleith(2825) on 2009-09-11 13:33:13 (Show Source):
You can put this solution on YOUR website!Assuming english alphabet and lower case and upper case count as one, then you have 26 letters.
So how many ways can you use 9 different letters?
First letter can be anyone of the 26.
The second one can't duplicate the first, so there are 25 you could choose
then 24, 23, 22, 21 ...
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Geometry_proofs/212632: This question is from textbook
If ray AB and ray CD intersect, then segment AB and segment CD intersect. How is this statement false? 1 solutions
Answer 160547 by vleith(2825) on 2009-09-10 20:14:28 (Show Source):
You can put this solution on YOUR website!the two rays could intersect at a point that is not on segment AB or segment CD or both. Net, the rays 'go on forever', so there are lots of points where the two culd intersect and not be on the segments
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Proportions/212495: a 6-foot tall man is standing near a tree on level ground, and the mans shadow is 4feet long, how many feet tall is the tree.(the tree is 18 feet_ 1 solutions
Answer 160462 by vleith(2825) on 2009-09-10 14:41:35 (Show Source):
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Triangles/212421: A certain triangle has area 6 cm^2. If you know that its base is one less than it height, what are the base and height of the triangle? 1 solutions
Answer 160415 by vleith(2825) on 2009-09-10 09:38:53 (Show Source):
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Vectors/212412: please could someone help me with this question?
A tea connoisseur has a collection of teapots that are scaled versions of the same design. The one-cup teapot is 10cm high. Choose the TWO options that are true statements.
A The two-cup teapot is 20cm high
B The eight-cup teapot is 20cm high.
C The nine-cup teapot is 30cm high.
D The 25cm high teapot is appropriate to make 20 cups of tea.
E The 16cm teapot is appropriate to make 4 cups of tea.
Thank you very much
Dawn 1 solutions
Answer 160411 by vleith(2825) on 2009-09-10 09:15:32 (Show Source):
You can put this solution on YOUR website!The amount of tea is a volume. So, in order to scale, each of three dimensions must scale in the same ratio as the single dimension you are given.
All that ends up saying is "the change in volume is the cube of the change in a single dimension".
For instance, if the pot is changed from 10cm to 20cm, then the scale has doubled. So you need to cube that to get the volume. Thus, a 20cm high pot will brew  =  cups.
A 30cm high pot will brew  cups
Do that same type of conversion and you can find the two answers that "fit".
If you can't get them, let me know.
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Numeric_Fractions/212109: This question is from textbook Elementary and Intermediate Algebra, Chapter
According to Dr. Aaron R. Folsom
of the University of Minnesota School of Public Health,
your maximum ideal waist size is directly proportional
to your hip size. For a woman with 40-inch hips, the
maximum ideal waist size is 32 inches. What is the
maximum ideal waist size for a woman with 35-inch hips? 1 solutions
Answer 160193 by vleith(2825) on 2009-09-09 08:59:02 (Show Source):
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Triangles/212114: A segment is divided into two parts having lengths in the ratio of 5:3. If the difference between the length of the parts is 6," find the length of each part.
x =
Segment 1 = (5x) = inches
Segment 2 = (3x) = inches 1 solutions
Answer 160188 by vleith(2825) on 2009-09-09 08:47:36 (Show Source):
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Travel_Word_Problems/211588: A man rides out into the country at a uniform rate of 30 miles per hour.
He rests 2 hours and then rides back at 20 miles per hour. He is gone 5
hours. How far did he go?
Please work me through this problem!
Thanks! 1 solutions
Answer 159874 by vleith(2825) on 2009-09-07 16:40:51 (Show Source):
You can put this solution on YOUR website!First thing, let's get rid of the 2 rest hours. That says the the man is actually moving for 3 hours.
You also know he goes as far at 30mph as he returns at 20mph.
Let the distance he goes each way be represented by d
Let the time at 30mph be given by t. Then the time at 20mph is

so

So the man travels at 30mph for 6/5 hour
 =  miles
Check your answer.
Does
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Travel_Word_Problems/211587: This question is from textbook
Can you please help me with this uniform motion problem? If the speed were increased by 10mph, a 420 mile trip would take 1 hr less time. How long will the trip take at the slower speed? Please show me all the steps and please get back to me before Tues. 10am.
Thank you guys 1 solutions
Answer 159871 by vleith(2825) on 2009-09-07 16:33:51 (Show Source):
You can put this solution on YOUR website!
You are told the distance is 420 miles.
Let the slow speed be represented by s (in miles per hours) and the slow time be represented by t (in hours)
So
Thus 
You are told that at  , the time will be
So 
Now substitute in the value you found for s above
 factor this or use the quadratic equation

For a product to equal 0, one or more of the terms multiplied must be 0. So
either  ot  that means either
 or  since the time cannot be negative, the time at the slow speed must be 7 hours.
Now check your answers. If the time is 7 hours then the slow speed must be 60mph
If the speed if 10mph faster, then the faster speed is 70mph.
At 70mph, the time is 420/70 = 6 hours. Which is an hour faster.
So there you have it.
happy Labor day -- and still int time for 10am tomorrow
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Equations/210732: What does it mean, both algebraically and graphically, when an ordered pair (x,y) is a solution to a system of two linear equations?
1 solutions
Answer 159196 by vleith(2825) on 2009-09-03 12:38:40 (Show Source):
You can put this solution on YOUR website!algebraically, it means that point is a solution to each equation
graphically, the point is the intersection of the two lines (assuming the lines are not 'the same line' or parallel lines, then they only intersect at a single point)
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Equations/210735: After solving a system of equations in two variables you surmise a solution, (x,y). How can you determine if the solution is correct?
1 solutions
Answer 159192 by vleith(2825) on 2009-09-03 12:35:21 (Show Source):
You can put this solution on YOUR website!Plug the x and y values into the original equation(s). If the result ends up being = (like 10=10 or 153=153) then the solution is correct
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Expressions-with-variables/210662: I am kind of lost on these problems please help
Solve find the value for the given variable Show all work and check answers showing all work
2x + 6 over 5 = x+4 over 3
3(2x+6) = 5(x+4)
6x +18 = 5x + 20 now I am confused and also don't know how to check answer
I would like to know if these are right and how to show the work to check answer
b/4 + b/3 = 7
12(b/4 + b/3) = 12(7)
12(b/4) + 12(b/3 = 84
3b + 4b = 84
7b = 84
b = 12
b/6 - b-2/8 = 4
LCD is 48
48(b/6 - b-2/8) = 48 (4)
48 (b/6 - 48 ( b-2/8) = 192
8b - 6(b-2) = 192
8b - 6b - 12 = 192
2b = 204
b = 102
1 solutions
Answer 159165 by vleith(2825) on 2009-09-03 06:34:57 (Show Source):
You can put this solution on YOUR website!Solve find the value for the given variable Show all work and check answers showing all work
2x + 6 over 5 = x+4 over 3
3(2x+6) = 5(x+4)
6x +18 = 5x + 20 now I am confused and also don't know how to check answer.
So far, so good. Collect like terms
 subtract 5x from both sides and subtract 18 from both sides
 simplify
2)
The work is correct. To check your answer, take your solution (12) and substitute it into the original equation. If the result is, in fact, equal, then your answer is correct. In this case
 substitute in x=12
 which is TRUE. so your answer is correct
b/6 - b-2/8 = 4
LCD is 48
48(b/6 - b-2/8) = 48 (4)
48 (b/6 - 48 ( b-2/8) = 192
 so far, so good. You have an error in the next step.
 should be  remember when expanding, a negative times a negative is a positive
2b = 180
b = 90
URL to check your answer --> http://www.wolframalpha.com/input/?i=+b%2F6+-+(b-2)%2F8+%3D+4
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Expressions-with-variables/210664: These are extra problems I need help to understand to bring up my grade please help I don't get it
Find the value for the given variable Show all steps and check answers showing all work. Not sure how to type in the problem.
a+1/6 = 2/a or a+1 over 6 = 2 over a
and
5/3x+1 = 3/3x-1 or 5 over 3x+1 = 3 over 3x-1
1 solutions
Answer 159162 by vleith(2825) on 2009-09-03 06:20:01 (Show Source):
You can put this solution on YOUR website! multiply both sides by a to clear the denominator on the right
 multiply both sides by 6 to clear the denominator on the left
 expand the left side
 subtract 12 from both sides
 factor or use the quadratic equation. Here is a good URL to help check your factoring -->http://72.3.253.76:8080/webMathematica3/quickmath/page.jsp?s1=algebra&s2=factor&s3=basic
 in order for a product to be 0, one or more terms in the product must be 0. So in our case, either  or 
So solving those two equations, says either  or  are solutions to the problem.
Substitute those values for a into the original equation to check your answers.
2)Use the same steps as above.
 Clear right side denominator
 Clear left side denominator
 this time, expand both sides
 collect like terms
 simplfy
 divide both sides by 6
 simplify
Here is a great website for math. You can use it to verify your work. For this problem the URL is --> http://www.wolframalpha.com/input/?i=5%2F(3x%2B1)+%3D+3%2F(3x-1)
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