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edjones answered: 7568 problems
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Quadratic_Equations/106822: Hello, I was given this question and I have no idea what it means.
Find all real solutions (m)^-4/3 = 16 ??????? Could you please help me with this one. Thank you, Paul 1 solutions
Answer 77723 by edjones(7569) on 2007-10-29 01:04:47 (Show Source):
You can put this solution on YOUR website!1/m^4/3=16 negative sign in front of exponent means the reciprocal.
We must reverse the process to see what we started with.
1/x =16 substitute x for m^4/3
x=1/16 multiply each side by x/16
1/16^3=1/4096
1/4096^(1/4)=1/8
m=1/8
Check:
(1/8)^-4/3=8^4/3
8^(1/3)=2
2^4=16
Ed
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Quadratic_Equations/106823: Hello, this is a tricky one.Find the domain of this function
f(x) = SR of 1/2x-1
(square root)
Where do I start? Thank you, Paul 1 solutions
Answer 77722 by edjones(7569) on 2007-10-29 00:37:56 (Show Source):
You can put this solution on YOUR website!f(x)=sqrt(1/2x-1)
1/2x-1 can't be less than 0 because square root of a negative number is not a real number.
x must be 2 or greater
x[2,infinity)
Ed
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Quadratic_Equations/106819: Hello, I was asked to perform this operation and I cannot find a similar example in my book. It looks like it should be easy, but I can't get started.
__4__ - _15_ When I previewed my question it doesn't look like it should
2x-4 5x It should be 4/2x-4-15/5x
Thank you for your help. Paul 1 solutions
Answer 77721 by edjones(7569) on 2007-10-29 00:30:31 (Show Source):
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Evaluation_Word_Problems/106691: A rectangular corral built with 190 m of fencing that inludes four separate grazing areas lies on a 962 m(square) rectangular plot of land. the fence that divides the grazing areas is parallel to two of the sides of the corral. if there is a 1 m strip of land between each side of the corral and the property line, find the dimesions of the corral. there may be more than one answer!!... 1 solutions
Answer 77647 by edjones(7569) on 2007-10-28 12:30:40 (Show Source):
You can put this solution on YOUR website!L*w=A
2L+2w=P
.
L*w=926
Our 2nd formula uses the perimeter formula plus the extra fencing to divide the corral in quarters. We have to use 3 instead of 2 for the coeficients of L and w because of the extra fencing to divide the coral into 4ths. we also have to subtract 2 from L and w to account for the 1 m strip of land not used for the corral
3(L-2)+3(w-2)=190
3L-6+3w-6=190
3L+3w-12=190
3L+3w=190+12
3L+3w=202
.
A) L*w=926
B) 3L+3w=202
.
L=926/w
3(926/w)+3w=202 substitute 926/w for L
2778/w+3w=202
2778+3w^2=202w multiply each side by w to eliminate the fraction.
3w^2-202w+2778=0
Quadratic Formula (see below): w=19.26 m, w= 48.06
I made L= 48.06 m and w= 19.26 m
.
Ed
| Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc) |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=7468 is greater than zero. That means that there are two solutions: .


Quadratic expression can be factored:

Again, the answer is: 48.0695984669789, 19.2637348663545.
Here's your graph:
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Trigonometry-basics/106690: A commercial airline is flying at 10km from the ground. It it approches the landing at an angle of 5 degrees from the ground, at what distance should the airplane begin it's descent? (answer is 114km from the airport, but need to know how to get there) 1 solutions
Answer 77641 by edjones(7569) on 2007-10-28 11:22:26 (Show Source):
You can put this solution on YOUR website!Construc a right triangle with hight 10 and angle opposite the height of 5 deg.
You need to know the length of the line adjacent to the angle (running along the ground).
cot=adj/opp
cot(5)=a/10
a=cot(5)*10
a=114.301 km
Ed
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Graphs/106668: my problem is I need to find the domain and range for f(x)=The Square Root of
25-(X^2)....all terms are under the square root symbol. ALSO where can I see if its increasing or decreasing? 1 solutions
Answer 77628 by edjones(7569) on 2007-10-28 10:40:54 (Show Source):
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Money_Word_Problems/106426: At Jones Realty each sale of a house results in 6% of the selling price being paid to the business. The selling agent then receives 60% of that amount as commission. If an agent sells a house for $225,000, what is the commission on the sale? 1 solutions
Answer 77519 by edjones(7569) on 2007-10-27 00:44:05 (Show Source):
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Geometry_Word_Problems/106510: Im suppose to show how
a-b/a+b = c-d/c+d
is proportional to
a/b=c/d 1 solutions
Answer 77517 by edjones(7569) on 2007-10-27 00:26:07 (Show Source):
You can put this solution on YOUR website!a-b/a+b = c-d/c+d
.
ac+ad-bc-bd=ac-ad+bc-bd multiply both sides by (a+b)(c+d) to eliminate fractions.
ad-bc=-ad+bc cancel off ac and bd
2ad=2bc add ad and bc to each side
ad=bc divide each side by 2
a/b=c/d divide each side by bd.
.
Ed
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Quadratic_Equations/106506: word problem for quadratic equation
Brendan buys a block of shares of Laser Technology for $1875. When the share price increases by $4 per share, he sells all but 15 of them for $1740. How many shares did he buy?
can anyone set-up the equation for this?? thanks for your help...
1 solutions
Answer 77515 by edjones(7569) on 2007-10-27 00:01:36 (Show Source):
You can put this solution on YOUR website!Let x=number of shares he bought. p=share price he paid
A) xp=1875
B) (p+4)(x-15)=1740
.
A) x=1875/p
B) px+4x-15p-60=1740 Expand
p*1875/p + 4*1875/p - 15p-60=1740 substitute 1875/p for x
1875+7500/p-15p-60=1740 cancel
1875p+7500-15p^2-60p=1740p multiply both sides by p to eliminate fraction.
-15p^2+75p+7500=0
15p^2-75p-7500=0
15(p^2-5p-500)=0
15(p-25)(p+20)=0
p= -20 is extraneous to this problem.
p=$25
x=1875/25= 75 shares Answer
Check:
60*29=$1740.
.
Ed
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Linear-equations/106473: Hello out there,I really need some help with some tough problems really bad,the first one is,Determine whether the system has one solution,no solution,or infinitely many solutions:y=2/3x and 2x-y=-4.The next one is,Determine whether the system has one solution,no solution,or infinitely many solutions:y=-x+2 and 3x+3y=6.The next one is,State whether the system is consistent and independent,consistent and dependent,or inconsistent:x+y=4 and 2x-y=-7.And the last one is,State whether the system is consistent and independent,consistent and dependent,or inconsistent:4x+2y=8 and 2x+y=1.Thanks to whoever can help me. 1 solutions
Answer 77485 by edjones(7569) on 2007-10-26 19:51:24 (Show Source):
You can put this solution on YOUR website!All you have to do to answer the above questions is get both equations in the slope-intercept form: y=mx+b
m is the slope if m is different in each equation then the system is consistent and the system has an answer and the lines cross on the graph.
If m is the same number (including sign) in both equations:
I) If b is different in both equations then there is no answer and the graph shows parallel lines and the system is inconsistent.
II) if b is equal in both equations then the equations are equal and consistent and has an infinate number of answers.
.
y=2/3x
2x-y=-4...-y=-2x-4...y=2x+4
m=2/3 in the 1st equ. and 2x in the 2nd so they are consistent and there is a solution.

.
y=-x+2
3x+3y=6...3y=-3x+6...y=-x+2
These are the same equation. infinate number of answers.
.
x+y=4...y=-x+4
2x-y=-7...-y=-2x-7...y=2x+7
Has a solution
.
4x+2y=8...2y=-4x+8...y=-2x+4
2x+y=1...y=-2x+1
slopes are equal; b's are different.
inconsistent, parallel lines

.
Not hard at all, once you know how to do them, huh.
.
Ed
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Human-and-algebraic-language/106472: find i six digit number in wich the first digit is one less than the second, the secound one less than the third, the fourth digit is one less than the fifth, and the fifth one is one less than the last. the second digit equals the sum of the last three digits and the third digit equals the sum of the secound and fourth digit. 1 solutions
Answer 77481 by edjones(7569) on 2007-10-26 19:10:06 (Show Source):
You can put this solution on YOUR website!a=b-1
b=c-1
d=e-1
e=f-1
b=d+e+f
.
d+e+f<10 So must be 1+2+3 or 2+3+4
b= 6 because if it were 9 then c would be 10
So, d+e+f=6
b=6
d=1
e=2
f=3
a=5
c=7
.
The number is: 567123
We didn't need the final clue.
Ed
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decimal-numbers/96861: Change each measurement to the given unit.
(1.)5 kg 240 g to kilograms
(2.) 11 L 17 mL to liters
(3.) 24 m 5 cm to centimeters
1 solutions
Answer 77417 by edjones(7569) on 2007-10-26 02:23:41 (Show Source):
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Equations/106360: In a 10 foot wide alley, two ladders lean against opposite walls. One Ladder reaches 30 feet up on the wall, while the other reaches 20 ffet up on the opposite wall. How high above the ground will the two ladders cross? 1 solutions
Answer 77416 by edjones(7569) on 2007-10-26 02:17:41 (Show Source):
You can put this solution on YOUR website!I assume that the ladders bases are in the corner of the side opposite which they are leaning.
L=longest ladder, s=shortest
cos(L)=10/30=1/3
cos^-1(1/3)=70.53 deg
.
cos(s)=10/20=1/2
cos^-1(1/2)=60 deg
.
Now we have a triangle with a base of 10 and we know the three angles 70.5,60 and 49.47
a/sin(A)=b/sin(B)
10/sin(49.47)=b/sin(60)
10*sin(60)/sin(49.47)=11.39 ft (one of the sides)
.
Now if you draw a line from the angle of the ladders crossing perpendicular to the base we have the height (h) of the triangle.
It is opposite the 70.53 deg angle and the 60 deg angle. It forms two right triangles. The 11.39 side is the hypotenuse of one of the right triangles.
sin(70.53)=opp/11.39
opp=sin(70.53)*11.39=10.74 ft Answer
.
Ed
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Triangles/106401: This question is from textbook
hi please help me i dont understand this problem
in equilateral triangle DEF, Measure of angle D = x+y
and measure of angle E = 2x-y
find x and y
please answer thanks a lott
1 solutions
Answer 77413 by edjones(7569) on 2007-10-26 00:57:14 (Show Source):
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Linear_Equations_And_Systems_Word_Problems/106393: My head has been deeply stuck on this one. i think that im confused about the process Please help me on this one:
So far you have 5 songs on your MP3 that take up 16 megabytes. the average song takes up about 3megabytes of space. this is represented by the function m= 16+3s
where s is the number of songs and m is the megabytes
A)Identify the domain and range
B)identify the domain and range if the MP3 can store up to 256 mb.
C) Suppose your MP3 can hold 512 mb of music. how does this change the domain and range of the function? 1 solutions
Answer 77412 by edjones(7569) on 2007-10-26 00:48:54 (Show Source):
You can put this solution on YOUR website!m=3s+16 s=number of songs, m=number of megabytes
I assume part of a song can be recorded.
.
A) domain is all real numbers >= 0, range is all real numbers >= 16
.
B) 256=3s+16...3s=240...s=80
domain is all real numbers from: 0=< s <= 80
range is 16 to 256
.
C) 512=3s+16...3s=496...s=165 1/3
domain is all real numbers from: 0=< s <= 165 1/3
Range is 16 to 512
.
Ed
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Rational-functions/106204: the problem is as follows=== Identify all asymptotes, the y intercept, all x intercepts for the graph f(x). Then scetch the graph.
f(X)= 2x^2-5x-3
---------
x^2-9
Thanks for your help 1 solutions
Answer 77287 by edjones(7569) on 2007-10-25 04:15:43 (Show Source):
You can put this solution on YOUR website!
Vertical assymptote is x when the denominator=0
Vertical assymptote= the line x= -3
Horizontal assymptote: since the degree of the polynomial is the same top and bottom it is the line 
y intercept (when x=0) y=1/3
x intercept (when y=0): x=-1/2
Ed
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Money_Word_Problems/106223: Mr. Jones sold 2 candies at $1.20 each. based on the cost, his profit on one was 20% and his lost on the other was 20%. On the sale of the candies, he gain or lost by how much? 1 solutions
Answer 77286 by edjones(7569) on 2007-10-25 03:46:32 (Show Source):
You can put this solution on YOUR website!let g be the cost of the candy he gained on.
let L be the cost of the candy he lost on.
.
g+.2g=1.20
1.2g=1.20
g=1.20/1.2
g=$1.00
.
L-.2L=1.20
.8L=1.20
L=1.20/.8
L=$1.50
.
His cost for the 2 candies was $2.50 and he sold them for $2.40
His loss was 10 cents on the deal.
.
Ed
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Exponents-negative-and-fractional/106245: This question is from textbook teach yourself algebra
x I understand from the book I have that when simplified you get the followin results: x = I understand how the letters are cancelled out what I do not understand is why the numbers6 and 3 disappear, the 14 halves to 7 and the 2 does not change? Pleae could you help me? 1 solutions
Answer 77284 by edjones(7569) on 2007-10-25 03:31:06 (Show Source):
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Miscellaneous_Word_Problems/106227: X baskets of strawberries were put on sale on Monday. The unsold baskets of any day were put on sale the next day. 1/3 of the baskets were sold on Monday. 2/3 of those put on sale on Tuesday were unsold. 8 baskets were put on sale on Wednesday. What is X? 1 solutions
Answer 77282 by edjones(7569) on 2007-10-25 03:15:11 (Show Source):
You can put this solution on YOUR website!2x/3 were put on sale on tues.
2x/3*2/3=4x/9 were put on sale on wed.
4x/9=8
4x=72
x=72/4
x=18
Check:
1/3 of 18 were sold on mon.
12 were put on sale on tues.
2/3 of 12 were unsold so there was 8 left to be put on sale wed.
Ed
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Volume/106243: how do you figure out what the cubic meters is from meters
the volume of a cube which is 5 meters per side
what is the right way to calculate it 1 solutions
Answer 77281 by edjones(7569) on 2007-10-25 02:55:26 (Show Source):
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