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#1 Re: Help Me ! » Need help solving two problems » 2010-05-02 16:56:50
Problem 2 :
So after you get x^2+80x+1555=0
then what?
#2 Re: Help Me ! » Need help solving two problems » 2010-05-02 16:52:35
The way you expressed problem one is correct
#3 Help Me ! » Need help solving two problems » 2010-05-02 14:08:27
- Slowlrnr
- Replies: 6
problem # 1
x+4*square root of x=5
________
problem # 2
The profit, p(x), earned by producing and selling x units is measured by the function
p(x)= -.05x^2 + 40x - 3 , where P(x) is measured in dollars.
a) Evaluate P(3) and explain what the input and output represent.
I answered 3 units sold for $112.50 profit?
b) Determine the profit that will be earned if 10 units are produced and sold.
I answered $347.00 ?
c) determine the number of units needed to be produced and sold to earn a profit of $797
I am stuck on this one. I think I am setting up the formula wrong.
#4 Help Me ! » I need a shove in the right direction » 2010-05-01 10:23:59
- Slowlrnr
- Replies: 1
I have become stuck in varies areas in solving the following problems. If you can help then I can see what/where I am having problems. Sorry but my parents are no help.
Determine the coordinates of the vertex for the graphs of the following function.
F(x)= 2x^2-10x+14
I calculated the H to be 2 1/2 using -b/2a
When I plugged H into the formula I got 6.12?
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Given f(x)=2x^2-x-3, determine the coordinates of the vertex and interceps. Sketch the graph.
I calculated X= -1 or X=1 1/2
H= 1/4
k= i got stuck
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Find the value(s) of X that satisfy each of the following inequalities. Express your solution in interval notation.
3x^2+5x >_ 2 ( the >_ is greater than not equal to )
I calculated x=1/3 , x=-2
so ( -infinity,-2] [1/3,infinity) ?
6x^2-24<7x
I got stuck in the quadratic equation
I got to 7+- square root of -527 all over 12 ?
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x+4 square root of x =5
I attempted to take all the terms to the 4th power to get rid of the square root which gave me
x^4+x=625 ?
Am I right?
#5 Re: Help Me ! » Word problems assistance » 2010-04-30 23:19:14
So what does the 3 represent in the walking equation? I see my error wih the multiplication but the question was asking for "how fast does she walk?".
#6 Help Me ! » Word problems assistance » 2010-04-30 16:11:50
- Slowlrnr
- Replies: 5
How would you set up the formula?
A farmer has 3000 feet of fencing and wishes to enclose a rectangular area. What is the maximum area he can enclose?
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Beth can walk six miles in the same time she can bike 32 miles.If her biking rate is one more than five times her walking rate, how fast does she walk?
Is it 6/x= 32/5x+1 ? if so , then x = 1/2? I then used f(1/2) = 5x+1 and got 3.5 . Is this correct and what does this 3.5 relate to ? I am confused..
Thank you for your time.
#7 Re: Help Me ! » Need help with area of rectangle question » 2010-04-14 16:34:48
Hi;
You have the quadratic:
w^2 + 3w - 40 = 0
You need to factor it. Can you think of 2 numbers that when multiplied equal -40 and when added equal 3?
These pages will help you:
http://www.mathsisfun.com/algebra/facto … atics.html
http://www.purplemath.com/modules/factquad.htm
The factorization will be of the form:
( w + ) ( w - ) = 0
So you are saying W = 5
and the length = 16?
#8 Re: Help Me ! » Need help with area of rectangle question » 2010-04-14 15:44:05
I am stuck from there.
#9 Help Me ! » Need help with area of rectangle question » 2010-04-14 15:34:42
- Slowlrnr
- Replies: 5
The length of a rectangular room is 6 feet longer than twice the width. The area is 80 sqaure feet. Find the length and the width of the room.
So L=2w+6
80=(2w+6)(w)
is this setup correct? Somewhere in my calculations I am getting stuck.
80=2w^2 +6w
40-3w=w^2
I am getting messed up somewhere.
Can you assist?
#10 Re: Help Me ! » Need expressed as an equation » 2010-04-01 03:14:06
Thanks.
Unfortunately, I have another issue with a word problem. I stink at these.
A tub takes three times as long to fill now that it has sprung a leak than it did before. All of the water will leak out of the tub in 1 hour. How long does it take the tub to fill with and without the leak?
Alright, I think I determined the formula "without the leak" to be:
1/T-1/60=1/(3T) and it came out to 40 minutes.
or should I have expressed this as
1/T-1/(3T)=1/60
I am having an issue with the "with the leak" setup. 
#11 Re: Help Me ! » Need expressed as an equation » 2010-03-31 10:39:44
Thanks. I hate English in my Math 
I solved the first problem but the second I ran into a snag.
I used 6X as the LCD which resulted in
x^3-6x=6
x^3-6x-6=0
I cannot factor that any lower. Did I do something wrong?
#12 Help Me ! » Need expressed as an equation » 2010-03-31 06:20:19
- Slowlrnr
- Replies: 4
1) Ten divided by the difference of a number and one equals the quotient of the number and two.
2) The ratio of six and a number squared, reduced by one, is equal to the reciprocal of the number.
Thank you for your time.
#13 Re: Help Me ! » Help with triangle angles » 2010-01-26 12:37:26
Thank you for the welcome and thank you for the explanation. I was making mathematical errors using percentages instead of just using the .3
That made it easier.
Thank you again
#14 Help Me ! » Help with triangle angles » 2010-01-26 12:01:16
- Slowlrnr
- Replies: 2
I am having trouble setting up the equation from this word problem.
the size of the smallest angle of a triangle is 30% of the size of the largest angle. The size of the third angle is 20 degrees more than the smallest angle/ Find each angle. ( the sume of all angles is 180 )
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