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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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Quadratic_Equations/210380: Use the quadratic formula to determine the x intercepts (if any) of the following function. Then evaluate the function for several values of x, and use the resulting points to graph the function. Show your work.
f(x)=7x^2-2
I have already come up with what I believe is the solution of the quadrtic,
x=0.534 x= -0.534.I don't understand how to get the other points on the graph and have it look like it's supposed to.
Thanks
1 solutions
Answer 158977 by vleith(2825) on 2009-09-02 11:10:02 (Show Source):
You can put this solution on YOUR website!You have the correct x intercepts. Now you need to find the minimum point. You can see by looking at the function that the value  will cause f(x) to be as small as it can get.
So calculate f(0)
 = 
Plot the points (0, -2), (0.534, 0) and (-0.534, 0)
Now draw a nice parabola thru them. If you need more points, just pick some x values (like 1 and -1), evaluate f(x) at those values for x and then plot those points too
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Coordinate-system/210385: without graphing, fing the minimum value
f(x)=3(x+12.68)^2-sqrt22 1 solutions
Answer 158974 by vleith(2825) on 2009-09-02 11:01:05 (Show Source):
You can put this solution on YOUR website!Without graphing, to find the minimum value, you need to look at the terms and see which one(s) can change. You know that  is a constant, so that one won't change. You can see that the first term  involves a factor of that includes a square. You know that the minimum a squared value can be is 0 (A squared value is always going to be positive or 0).
So the minimum value occurs when the first term is 0.
So what value of x makes

When x = -12.68, then
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percentage/210375: Compute the requested value. Choose the correct answer.
If the selling price is $75.50 and includes the cost plus 5% of the cost, then what is the cost? 1 solutions
Answer 158963 by vleith(2825) on 2009-09-02 10:21:33 (Show Source):
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Graphs/210378: Hi,
I'm having a little difficulty completing my project for algebra. Here's my question........
In a plotted graph, the x-axis represent weight and the y-axis represent miles. What would a slope of -13/22 mean?
Is it for every 13 miles decreasing the weight decreases by 22 pounds?????? 1 solutions
Answer 158962 by vleith(2825) on 2009-09-02 10:20:04 (Show Source):
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Probability-and-statistics/210376: i can not figure this one out. can someone just tell me how to calculate.7 of 20,000. i get 14000 and that would only leave 6,000 which isnt an option. help please!!!
A contractor is considering a sale that promises a profit of $ 20,000 with a probability of .7 or a loss (due to bad weather, strikes, and such) of $ 3000 with a probability of .3. What is the expected profit?
A)
$ 16,100
B)
$ 17,000
C)
$ 13,100
D)
$ 14,000
1 solutions
Answer 158959 by vleith(2825) on 2009-09-02 10:12:15 (Show Source):
You can put this solution on YOUR website!I think the question here is what does the contractor expect when a large enough set of similar deals happens.
You are told that contractor expects to make 20,000 70% of the time and lose 3000 30% of the time.
So what can the contractor expect if he/she does a bunch of these deals?
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Numbers_Word_Problems/210342: in how many ways can 72 be expressed as product of two-digit Even numbers 1 solutions
Answer 158947 by vleith(2825) on 2009-09-02 06:21:27 (Show Source):
You can put this solution on YOUR website!This is a really bad question.
I assume what they are really asking is "How many ways can 72 be expressed as a product of two-digit even Integers". That answer would be:
None.
For a quick check, use the smallest 2 digit even number --> 10
If 10 is used, the 'other number' would be 7.2.
Any even number larger than 10 would make the other number smaller than 7.2. Since 7.2 is NOT a two digit integer, then the answer is "none".
So what makes this a bad question?
The fact that the problem asked for two digit even 'numbers'. Since 10 and 7.2 both contain two digits, and are both even, then they work. Since there is going to be a "really big' number of similar two-digit (albeit non-integral) numbers, makes the answer to this one a mess.
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Graphs/209800: Why does the equation y=(0.5)^x not have an x- intercept, using algebra? 1 solutions
Answer 158586 by vleith(2825) on 2009-08-31 06:15:31 (Show Source):
You can put this solution on YOUR website!In order for a point to be an 'x-intercept', the y coordinate must be 0.
Let's substitute in y=0 and then attempt to solve for x

The Log(0) is undefined, so y cannot be 0.
You can also try it another way
As x increases, the value of  approaches 0. However, 0 is the asymptote --> y never 'quite gets to 0, just really really close'
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Miscellaneous_Word_Problems/207887: A rectangular deck has an area of (x2 + 6x + 8) square feet. If its width is (x + 2) feet then:
a. Find its length in terms of ‘x’.
b. If x = 3, what will be the area, length and width in feet.
1 solutions
Answer 157242 by vleith(2825) on 2009-08-22 07:44:21 (Show Source):
You can put this solution on YOUR website!Area = (x^2 + 6x + 8)
Width = (x +2)
Area = Length * Width
Area/Width = Length
If x=3 what are the area, length and width
Width = (x+2) = 3+2 = 5
Length = (x+4) = (3+4) = 7
Area = x^2 +6x + 8 = 3^2 + 6*3 + 8 = 9 + 18 + 8 = 35
Area = Length*Widht = 7 * 5 = 35
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Miscellaneous_Word_Problems/207888: If a ball is thrown upwards at 40 feet per second from a rooftop 24 feet above the ground, then its height above the ground t seconds after it is thrown is given by h = - 16 t2 + 40 t + 24.
a. Rewrite the above formula with the polynomial on the right hand side factored completely.
b. Use the factored version of the formula to find h when t = 3.
1 solutions
Answer 157241 by vleith(2825) on 2009-08-22 07:40:26 (Show Source):
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Graphs/207794: i posted these problems 4 days ago,but haven't received a response.could someone please help me.Thanks.
sketch the graphs,using the roots to find the function and the turning point
1.x = -8, x = 4
2.x = -3, x = 3
thanks for the help.hagd
1 solutions
Answer 157180 by vleith(2825) on 2009-08-21 15:19:23 (Show Source):
You can put this solution on YOUR website!You are given roots, so you can figure out the quadratic. I will do the first one, you can use the same process to do the second one
1) roots are x=-8 and x=4
You know that at the roots, the value of the function is 0
You also know that for any product to equal zero, one or more terms in that function must be 0.
Thus
x =-8
x+8 = 0
x=
4
x-4=0
Now you have the two terms for your equation

This is the equation for the first problem. Since is it q quadratic, you know it is a parabola that opens up (opens up since the x^2 term is positive). You also know that the 'turning point' will be halfway between the two root. Since the roots are 12 units apart, the 'turning point' will be 6 units from each root.
-8+6 = -2
4-6 = -2
So find the value of f(x) when x=-2 and you'll have the minimum.

So the 'turning point is the point (2,-20)
Plot the funtion here --> http://www.wolframalpha.com/input/?i=x^2+%2B+4x+-+32+
Now do the same process for the other one. I am sure you can do it. If you still have questions, drop me an email
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Graphs/207795: please help. I am trying to teach this to my daughter,but I need step by step instructions in order to do so .Thanks
solve for the unknown
1.5 = sqrt a + 2 (the 2 is not inside the sqrt symbol)
2.33 + 4 sqrt a = 6 sqrt a - 7 (7 is not inside the sqrt symbol)
thanks for the help. I really appreciate it. 1 solutions
Answer 157179 by vleith(2825) on 2009-08-21 15:09:08 (Show Source):
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test/207798: Please help me with this problem:
Write and solve an equation to find the value of x.
4.8, 1.6, 5.2, x; mean 3.7
Thanks! 1 solutions
Answer 157177 by vleith(2825) on 2009-08-21 15:03:13 (Show Source):
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Volume/207749: Silver metal has a density of 10.5g/cm^3. A solid sphere of silver has mass of 0.295 g. What is the diameter of the silver piece, in mm? The volume of a sphere is V= (4/3)3.14*r^3 . I do not even know where to start with this. 1 solutions
Answer 157133 by vleith(2825) on 2009-08-21 04:52:20 (Show Source):
You can put this solution on YOUR website!You are given the density of silver and told about a silver sphere that has a mass of 0.295g.
So you need to find the diameter of a sphere that with that mass.
First let's figure out what volume the sphere must be.
You are asked to find the sphere's diamter in mm. So let's convert the volume to (mm)^3
There are 10 mm/cm, so the converion from (mm)^3/(cm)^3 = 10*10*10 = 1000(mm)^3/(cm)^3

You are ready ro solve
Now just grind out the value for r.
Once you have that, you need to remember you were asked for the diameter. So just double the radius and you are there.
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Miscellaneous_Word_Problems/207607: A toy manufacturer produces model cars which are similar in every way to the actual cars. If the ratio of the door area of the model to the door area of the car is 1:2500, find
the ratio of the capacites of their petrol tanks 1 solutions
Answer 156995 by vleith(2825) on 2009-08-20 10:04:44 (Show Source):
You can put this solution on YOUR website!First find the linear scale.
You are told two areas are scaled at 1:2500
You know area is measured in squared linear dimension.
SO, what is the sqaureroot of 2500?
Thus the linear scale is 1:50
Now, you are asked about 'capacity of the petrol tanks'. That is a volume. And volume are in cubic dimensions.
So the scale needs to be cubed

wow
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Coordinate-system/207611: 3x + 4y =12 graph the equation on the coordinate system 1 solutions
Answer 156993 by vleith(2825) on 2009-08-20 10:00:30 (Show Source):
You can put this solution on YOUR website!The given equation is a line. So you need to find two points and then plot them.
For me, the easiest points to calculate are ones that have a 0 in one of the coordinates.
So let's find the point with where x=0

So one point is (0,3)
Now find the point with a y coordinate of 0

Another point is (4,0)
Now, plot those two points (0,3) and (4,0).
Then draw the line that contains those two points.
See this URL for a plot --> http://www.wolframalpha.com/input/?i=3x+%2B+4y+%3D12
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