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Earlsdon answered: 6288 problems
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Numeric_Fractions/7020: How do you change .78 repeating and .66 repeating into a fraction?
1 solutions

Answer 3836 by Earlsdon(6294) About Me  on 2005-08-10 23:48:42 (Show Source):
You can put this solution on YOUR website!
Change 0.7878... to a fraction.
Let n = 0.7878... Multiply both sides by 100 (by 100 when there are two repeating decimal digits)
100n = 78.7878... Subtract n from 100n.
99n = 78 Divide both sides by 99
n = 78/99 but n is 0.7878..., so
0.7878... = 78/99
Similarly with 0.66...
Let n = 0.66... Multiply both sides by 10 (by 10 when there is only one repeating digit)
10n = 6.66... Subtract n from 10n.
9n = 6 Divide both sides by 9.
n = 6/9 but n is 0.66..., so
0.66... = 6/9
Check using your calculator. 78/99 = 0.787878... and 6/9 = 0.6666...


Radicals/7007: Please help me find the (sqrt of 3/2)

1 solutions

Answer 3830 by Earlsdon(6294) About Me  on 2005-08-10 18:49:53 (Show Source):
You can put this solution on YOUR website!
Unfortunately, you cannot find the exact value of sqrt%283%2F2%29 because it is an irrational number that results in a non-repeating, non-terminating decimal.
Your calculator can give you an approximate value:
sqrt%283%2F2%29+=+1.22474487139... approximately.


Numbers_Word_Problems/7006: A man died and left the following instructions for his fortune
Half went to his wife
1/7 of what was left went to his son
2/3 of what was left went to his butler
the man's pet pig got the remaning $2000
How much money did the man leave behind altogether?
1 solutions

Answer 3829 by Earlsdon(6294) About Me  on 2005-08-10 18:43:05 (Show Source):
You can put this solution on YOUR website!
Let x = the deceased man's fortune.
To his wife, he leaves (1/2)x
To his son, he leaves (1/7) of (1/2)x
To his butler, he leaves (2/3) of ((1/7) of (1/2)x)
To his pig, he leaves the remaining $2,000.00
All these amounts should add up to $x, the deceased man's fortune.
(1/2)x + (1/7)(1/2)x + (2/3)(1/7)(1/2)x + $2,000.00 = $x Simplify and solve for x. Factor an x from the first three terms.
x(1/2 + 1/14 + 2/42) + $2,000.00 = $x Add up the fractions. The common denominator is 42.
x(21/42 + 3/42 + 2/42) + $2,000.00 = $x
x(26/42) + $2,000.00 = $x Simplify the fraction.
x(13/21) + $2,000.00 = $x Subtract x(13/21) from both sides.
$2,000.00 = $x - x(13/21)
$2,000.00 = $x(8/21) Multiply both sides by the multiplicative inverse of 8/21
$2,000.00(21/8) = $x
$x = $5,250.00 The deceased man's fortune.


Radicals/6999: what is and how i solve it please with a cherry on top!!!!
2x-3
_____ =4/7
4x-5

Rachel
1 solutions

Answer 3827 by Earlsdon(6294) About Me  on 2005-08-10 18:22:21 (Show Source):
You can put this solution on YOUR website!
Well...I have never solved an equation with a cherry on top, but there's always a first time.
%282x-3%29%2F%284x-5%29+=+4%2F7
Cross-multiply;
7%282x-3%29+=+4%284x-5%29
Simplify and solve for x.
14x-21+=+16x-20
Subtract 14x from both sides.
-21+=+2x-20
Add 20 to both sides.
-1+=+2x
Divide both sides by 2.
x+=+-1%2F2
Check:
%282%28-1%2F2%29-3%29%2F%284%28-1%2F2%29-5%29 = %28-1-3%29%2F%28-2-5%29 = %28-4%29%2F-7 = 4%2F7


Square-cubic-other-roots/6931: directions: write the polynomial function having given the roots.
(i don't know what this means.)
-1/2,2/3 (its shown as fractions)
thank you.
1 solutions

Answer 3805 by Earlsdon(6294) About Me  on 2005-08-10 00:52:19 (Show Source):
You can put this solution on YOUR website!
This means: If you had a polynomial (say, in x) and you solved it to find its roots and they turned out to be: x = -1/2 and x = 2/3, what would that polynomial look like?
Well, first, since there are two roots, the polynomial must be a quadratic function like: f(x) = ax^2 + bx + c
Now, if you have the roots to a quadratic function, you can form the factors of that function by recalling how you get the roots to a quadratic function in the first place.
If the roots are x = -1/2 and x = 2/3 then the factors would be:
(2x + 1) and (3x - 2)
Why is this?
Because to get the roots of the quadratic, you had to set each of the factors equal to zero, as in: (2x + 1) = 0, so x = -1/2 and (3x - 2) = 0, so x = 2/3
Now you have the factors of the quadratic function, you can find the function itself by multiplying these factors, (x + 1/2)(x - 2/3).
If you do this, you will get:
f%28x%29+=+6x%5E2+-+x+-+2
Check, using FOIL:
%282x+%2B+1%29%283x+-+2%29+=+6x%5E2+-+4x+%2B+3x+-+2+=+6x%5E2+-+x+-+2


Numbers_Word_Problems/6924: 1/2 kids have left party
18 kids are standing around
1/3 are dancing
how many kids were originally at party
1 solutions

Answer 3793 by Earlsdon(6294) About Me  on 2005-08-09 21:10:05 (Show Source):
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Let x be the number of kids originally at the party.
Then:
(1/2)x + 18 + (1/3)x = x Simplify and solve for x.
(1/2)x + (1/3)x + 18 = x Add the fractions of x, common denominator is 6.
(3/6)x + (2/6)x + 18 = x
(5/6)x + 18 = x Subtract (5/6)x from both sides.
18 = x - (5/6)x
18 = (1/6)x Multiply both sides by 6.
x = 108 The number of kids originally at the party.
Check:
(1/2)(108) + 18 + (1/3)(108) = 54 + 18 + 36 = 108


Percentage-and-ratio-word-problems/6770: This is a word problem involving ratios that I have been struggling with for a couple of hours now. Can you please help me.
The ratios of teachers to students at Elaine's school is 4 to 52. If there are 27 teachers at this school, then how many students are there? write a complete solution.
This what I have been trying: 4/52 = x/27, cross multiplied and 52x = 108, but it is not coming out right.
1 solutions

Answer 3733 by Earlsdon(6294) About Me  on 2005-08-07 23:38:19 (Show Source):
You can put this solution on YOUR website!
You have the right idea but the second ratio of your proportion is inverted.
Remember to keep like-items in the tops and like-items in the bottoms of the ratios.
Teachers/students = 4/52 You had this correctly shown.
Let x = # of students, so you want to see the number of teachers on top and the number of students (x) on the bottom.
27/x
The proportion looks like:
4/52 = 27/x Solve for x by cross-multiplying.
4x = (52)(27) Divide both sides by 4.
x = 1404/4
x = 351 This is the number of students.
Check:
4/52 = 27/351 Reduce the fractions.
1/13 = 1/13



Linear_Equations_And_Systems_Word_Problems/6773: a college student earned $8800 working as a waiter. the student invested some of the money at 7% and the rest at 6%, if the student recieved a total of $560 in interest at the end of the year, how much was invested at 7%?
This is the formula I used: principal multiplied by rate = interest OR x(.07) = .07x then I added 8800 - x(.06) = 560 which showed as:
.07x + 8800 - x(.06) = 560
I tried to solve for x and got 8240. I know I'm doing something wrong. can you help?
Sandy
1 solutions

Answer 3732 by Earlsdon(6294) About Me  on 2005-08-07 23:26:12 (Show Source):
You can put this solution on YOUR website!
Well, you started out ok but when you got to the line: 8800 - x(.06) = 560, this is where your mistake lies.
It should have been: (8800 - x)(.06) This is 6% of the total amount minus that invested at 7%
So, you should have:
.07x + (8800 - x)(.06) = 560 Solve for x.
.07x + (.06)(8800) - .06x = 560 Simplify.
.07x - .06x + 528 = 560
0.1x = 32
x = $3200 The amount invested at 7%


Coordinate-system/6761: Hi~
I am really having issues with the slope intercept equations and would like your assisance with the below question:
The line through (2,-3) that is perpendicular to the line 5x + 3y = 9
Thank you,
-Kate
1 solutions

Answer 3729 by Earlsdon(6294) About Me  on 2005-08-07 18:00:01 (Show Source):
You can put this solution on YOUR website!
The equation of the line that passes through the point (2, -3) and is perpendicular to the line whose equation is: 5x + 3y = 9 can be found by recalling that perpendicular lines have slopes that are the negative reciprocal of each other.
So, you need to determine the slope of the given line and then find the negative reciprocal of it to get the slope of the new line.
Put the given equation into the slope-intercept form: y = mx + b
5x + 3y = 9 Subtract 5x from both sides.
3y = -5x + 9 Divide both sides by 3.
y = (-5/3) + 3 The slope of the given line is: m = -5/3 The negative reciprocal of -5/3 is 3/5 and this is the slope of the new line.
So, for the new line you can write: y = (3/5)x + b Now you need to find b, the y-intercept.
This done by substituting the x and y coordinates from the given point (2, -3) into y = (3/5)x + b and solving for b.
-3 = (3/5)2 + b Solve for b.
-3 = 6/5 + b Subtract 6/5 from both sides.
(-15/5)-(6/5) = b
-21/5 = b
Now you can write the equation of the new line: y = (3/5)x - 21/5
You can check this by seeing that the given point, (2, -3) satisfies this equation and by seeng that the slope of this line is the negative reciprocal of the slope of the given line.
This is left as an exercise for the student. If you have any further issues with this, please call again.


Geometry_Word_Problems/6765: An angle's measure is 24 degrees less than that of its supplement. how would I measure find the measure of the triangle
1 solutions

Answer 3728 by Earlsdon(6294) About Me  on 2005-08-07 17:23:56 (Show Source):
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Well, let the angle be A. The supplement of angle A is (180 - A) degrees. The problem says that the measure of angle A is 24 degrees less than (180-A).
So we have: A = (180-A) - 24. Solve for A
A = 180 - A - 24 Add A to both sides.
2A = 180 - 24
2A = 156 Divide both sides by 2.
A = 78 degrees.
A = (180-78)-24
A = (102)-24
A = 78 degrees.
Check:
A = (180-A)-24
A = (180-78)-24
A = (102)-24
A = 78


Equations/6766: Please provide solution and explanation for the flwg:
X/180-x = 1/8
Don't understand how to eliminate fractions.
Thank you

1 solutions

Answer 3727 by Earlsdon(6294) About Me  on 2005-08-07 17:08:29 (Show Source):
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flwg???
Solve: x/(180 - x) = 1/8 or (x/180) - x = 1/8? It's probably x/(180-x) = 1/8
x/(180-x) = 1/8 Multiply both sides by (180-x)
x = (180-x)/8 Multiply both sides by 8.
8x = 180-x Add x to both sides.
9x = 180. Divide both sides by 9.
x = 20
Check:
20/(180-20) = 20/160 = 1/8


test/6763: I need help solving this word problem:
The sum of two numbers is 10. Their product is -24. Find the numbers. Write a complete solution
1 solutions

Answer 3726 by Earlsdon(6294) About Me  on 2005-08-07 16:57:00 (Show Source):
You can put this solution on YOUR website!
Try this!
Let the two numbers be x and y.
Then:
x + y = 10 Rewrite as: x = 10 - y and substitute into equation below.
xy = -24.
(10 - y)Y = -24 Solve for y.
10y - y^2 = -24 Add 24 to both sides and put into standard form.
y^2 - 10y - 24 = 0 Solve the quadratic by factoring.
(y + 2)(y - 12) = 0 Apply the zero product principle.
y + 2 = 0, y = -2
y - 12 = 0, y = 12
Now substitute these values of y into the original equations:
x = 10 - y
x = 10 - (-2)
x = 12
And:
x = 10 -y
x = 10 - 12
x = -2
The two numbers are: -2 and 12
Check:
12 + (-2) = 10, and
12(-2) = -24




Radicals/6739: sqrt(5x+6)-sqrt(3x-2)=2 solve for x.
please show all the steps involved. thanks!
1 solutions

Answer 3719 by Earlsdon(6294) About Me  on 2005-08-06 22:17:38 (Show Source):
You can put this solution on YOUR website!
Solve:
sqrt%285x%2B6%29-sqrt%283x-2%29+=+2 Add sqrt%283x-2%29 to both sides.
sqrt%285x%2B6%29+=+2+%2B+sqrt%283x-2%29 Square both sides.
%285x%2B6%29+=+4+%2B+4sqrt%283x-2%29+%2B+%283x-2%29 Simplify.
5x%2B6+=+2+%2B+3x+%2B+4sqrt%283x-2%29 Subtract 3x from both sides.
2x%2B6+=+2+%2B+4sqrt%283x-2%29 Subtract 2 from both sides.
2x%2B4+=+4sqrt%283x-2%29 Square both sides.
4x%5E2+%2B+16x+%2B+16+=+16%283x-2%29 Simplify.
4x%5E2+%2B+16x+%2B+16+=+48x+-+32 Subtract 48x from both sides.
4x%5E2+-+32x+%2B+16+=+-32 Add 32 to both sides.
4x%5E2+-+32x+%2B+48+=+0 Divide both sides by 4.
x%5E2+-+8x+%2B+12+=+0 Solve by factoring.
%28x+-+2%29%28x+-+6%29+=+0 Apply the zero product principle.
x - 2 = 0, x = 2 or
x - 6 = 0, x = 6


logarithm/6738: I am having trouble finding the y intercept on this problem. I have come up with an answer but not sure if its correct.
Heres the problem...
2x - 5y = -10
Thank you for any help you can provide.
1 solutions

Answer 3718 by Earlsdon(6294) About Me  on 2005-08-06 21:50:01 (Show Source):
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The simplest way to find the y-intercept is to let x = 0 and solve for y.
2x+-+5y+=+-10 Let x = 0 Recall that the y-axis crosses the x-axis at x = 0.
-5y+=+-10 Divide both sides by -5.
y+=+2
The y-intercept is at (0, 2)


Quadratic_Equations/6736: Can somebody show me how to find the coordinates of the vertex of the graph of+2%5E2-6x%2B2+ ?
Thank you!
1 solutions

Answer 3716 by Earlsdon(6294) About Me  on 2005-08-06 21:39:23 (Show Source):
You can put this solution on YOUR website!
There are several ways to find the coordinates of the vertex of a parabola.
I'm assuming that there is a typographical error in your question.
You probably meant to type:
y+=+x%5E2+-+6x+%2B+2
If not, your question is meaningless.
If this is the equation you intended, then read on.
1) You could graph the equation and find the location of the vertex of the parabola, or
2) You could put the equation into the form:
y+=+a%28x-h%29%5E2+%2B+k
and read the coordinates of the vertex from: (h, k)
This method requires that you perform an operation known as "completing the square".
3) You could put your equation into standard form ax%5E2+%2B+bx+%2B+c+=+0. Then find the x-coordinate of the vertex which is located at -b/2a.
Then you could get the y-coordinate by substituting the x-value into the equation y+=+x%5E2+-+6x+%2B+2 and solve for y.
Here's method 2.
Set you equation equal to zero.
x%5E2+-+6x+%2B+2+=+0 Subtract 2 from both sides.
x%5E2+-+6x+=+-2 Add the square of half the x-coefficient (-3)^2 = 9 to both sides.
x%5E2+-+6x+%2B+9+=+7 Factor the left side.
%28x+-+3%29%28x+-+3%29+=+7 Add 7 to both sides.
%28x+-+3%29%5E2+-+7+=+0 You now have the equation in the a(x-h)^2 + k form
%28x+-+h%29%5E2+%2B+k h = 3 and k = -7
The coordinates of the vertex are: (h, k) or (3, -7)


Linear_Algebra/6688: HI,
I have the following vertices of a rectangle: (-2,1), (1,4), (3,2), and (0,-1). How do I find the length of the diagonal of the rectangle?
1 solutions

Answer 3671 by Earlsdon(6294) About Me  on 2005-08-05 21:32:21 (Show Source):
You can put this solution on YOUR website!
First, you'll need to find the coordinates of opposite corners of the rectangle. This is best done by sketching the rectangle on graph paper using the coordinates of the given vertices.
According to my sketch, the coordinates of the opposite corners are:
(-2, 1) & (3, 2)
(0, -1) & (1, 4)
Use the distance formula to find the distance between one pair of opposite corners:
d+=+sqrt%28%28x2-x1%29%5E2+%2B+%28y2-y1%29%5E2%29
Take either pair of coordinates and substitute the appropriate x, y values into the distance formula and solve for the distance, d. Let's take the second pair of points, (0, -1) & (1, 4)
d+=+sqrt%28%281+-+0%29%5E2+%2B+%284+-+%28-1%29%29%5E2%29
d+=+sqrt%281%5E2+%2B+5%5E2%29
d+=+sqrt%2826%29
d+=+5.1


Linear-systems/6670: How do you factor: x^3 - 8 (x cubed minus 8)
1 solutions

Answer 3669 by Earlsdon(6294) About Me  on 2005-08-05 21:12:52 (Show Source):
You can put this solution on YOUR website!
You'll notice that the given expression is the difference of two cubes:
x^3 and 2^3
%28x%5E3-8%29=%28x%5E3-2%5E3%29
The difference of two cubes is factored as follows:
%28A%5E3+-+B%5E3%29+=+%28%28A-B%29%28A%5E2%2BAB%2BB%5E2%29%29
In the given expression: A = x and B = 2
%28x%5E3-8%5E3%29+=+%28x-2%29%28x%5E2%2B2x%2B4%29


Miscellaneous_Word_Problems/6684: You already answered one of my other questions like this, but i'm not sure what to do about this one. I've asked a couple people what they thought that i should do, and they both gave me different ideas of how to do the problem..so i have two different answers that don't look so right....so heres my question and answer if you would like to help me again. THanks.
My question says to remember the formula 1020 sqrt P (1-.01 sqrt P)=G. If P is the population in thousands. this formula is the amount of water in gallons per minute the city needs.
Question: A city has about 37,550 people. How many gallons per minute must the city's pumps be able to supply?
My two answers: 185356.19 or 37937.5

1 solutions

Answer 3665 by Earlsdon(6294) About Me  on 2005-08-05 17:58:30 (Show Source):
You can put this solution on YOUR website!
You can check my previous answer to a similar problem, but again, all you need do is to substitute P = 37.55 (thousands)(that's 37,550) into the given formula and grind away.
G+=+%0D%0A1020%28sqrt%2837.55%29%281-.01sqrt%2837.55%29%29%29
G+=+%286250.36%29%280.9387%29
G+=+5867.21 Gallons per minute.


percentage/6673: WHAT IS THE FORMULA TO FIGURE OUT WHEN YOU GET A RAISE WHAT THE PERSANTAGE IS.
EXAMPLE IF A PERSON MAKES $12.27 PER HOUR AND NOW THEY MAKE $12.62 PER HOUR HOW DO YOU FIGURE WHAT % YOUR RAISE IS?
1 solutions

Answer 3664 by Earlsdon(6294) About Me  on 2005-08-05 17:14:10 (Show Source):
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You can do it this way:
First, find the amount of the raise by subtacting the old hourly rate from the new hourly rate.
$12.62 - $12.27 = $0.35 per hour.
Next, divide the amount of the raise by the old hourly rate and multiply the result by 100 to get the percent increase.
[($0.35)/($12.27)](100) = (0.285348...)(100) = 2.85% increase.


Geometric_formulas/6681: If I know the length of a cord of a circle and the distance from the center of the cord to the edge of the circle. How do I find the radius of the circle. Thanks. Jim
1 solutions

Answer 3663 by Earlsdon(6294) About Me  on 2005-08-05 16:56:45 (Show Source):
You can put this solution on YOUR website!
Lacking a graphics capability, I'll try to explain in words how to go about this solving this problem. Perhaps you can draw the diagram yourself from the description below:
Draw a circle. Then draw two radii separated by some angle (the size of the angle is not crucial to solving).
Let's call the radius, R.
Now draw the chord connecting the two ends of the radii.
Let's call this C (for chord).
Now draw a third radius that bisects the chord.
So now each half of the chord is length C/2
The known distance from the chord to the circumference of the circle can be x.
So, what we need is an equation that relates the radius, R, to the length of the chord, C, and the distance, x.
If your diagram is correct, it should show inside the circle, a triangle formed by the first two radii and the chord.
The third radius exactly bisects this triangle into two congruent right triangles.
The hypotenuse of the right triangle is just radius, R.
The base of the right triangle is just half the length of the chord or C/2.
The height of the right triangle is R - x.
Now we can use the Pythagorean theorem to solve the problem.
R%5E2+=+%28C%2F2%29%5E2+%2B+%28R+-+x%29%5E2
Now we need to solve for R.
Simplifying:
R%5E2+=+%28C%5E2%2F4%29+%2B+%28R%5E2+-2Rx+%2B+x%5E2%29
Subtracting R^2 from both sides, we get:
0+=+%28C%5E2%2F4%29+-+2Rx+%2B+x%5E2
Adding 2Rx to both sides:
2Rx+=+%28C%5E2%2F4%29+%2B+x%5E2
Dividing both sides by 2x:
R+=+%28C%5E2%2F8x%29+%2B+%28x%2F2%29
This simplifies to:
R+=+%28C%5E2+%2B+4x%5E2%29%2F%288x%29
Since you know the length of the chord, C, and the distance, x, you can find the radius, R.



Miscellaneous_Word_Problems/6676: The formula that i was given is: 1020 sqrt P (1-.01 sqrt P)=G. If P is the population in thousands, this formula is the amount of water in gallons per minute the city needs......
Question: A city had a population of 43,250 people five years ago. Since then the population increased by 2250 people. How many more gallons per minute had to be added to the city's pumping capacity?
1 solutions

Answer 3662 by Earlsdon(6294) About Me  on 2005-08-05 16:10:31 (Show Source):
You can put this solution on YOUR website!
To solve this problem, you need to substitute P=2250 (as P= 2.25 thousands) into the equation and grind away.
G+=+1020sqrt%28P%29%281-.01sqrt%28P%29%29
G+=+1020sqrt%282.25%29%281-.01sqrt%282.25%29%29
G+=+1020%281.5%29%281-.01%281.5%29%29
G+=+%281530%29%280.985%29
G+=+1507.05 Gallons per minute.


absolute-value/6613: I am having a hard time with Variation, Progression, and Theorems. My question is Use the remainder theorem to determine the remainder when 5w^3 -2w+10 is divided by w+3?
Can someone please help me, I have already tried to answer this question on my own and cannot seem to get the right answer? Please?
1 solutions

Answer 3625 by Earlsdon(6294) About Me  on 2005-08-04 23:43:04 (Show Source):
You can put this solution on YOUR website!
The remainder theorem states:
If a polynomial P(x) is divided by (x-a), where a is a constant, then the remainder is P(a).
Starting with your polynomial: P%28w%29+=+5w%5E3+-+2w+%2B+10 and the given divisor: (w+3), you should be able to find the remainder by noting that, in this case, a = -3.
The remainder then should be P(-3) Let's find out.
P%28-3%29+=+%285%28-3%29%5E3+-+2%28-3%29+%2B+10%29
P%28-3%29+=+%285%28-27%29+%2B+6+%2B+10%29
P%28-3%29+=+%28-135+%2B+16%29
P%28-3%29+=+-119
To check this solution, you will need to perform the division, either by long division or by synthetic division.
I have done this and indeed, -119 is the remainder after dividing the given polynomial by w+3


Quadratic_Equations/6639: Find three unit fractions that have a sum of 11/18
I'm not sure if this is what they are asking: 5/6 + 3/6 + 3/6=11/18
Would this be an answer? Thanks
1 solutions

Answer 3622 by Earlsdon(6294) About Me  on 2005-08-04 23:04:16 (Show Source):
You can put this solution on YOUR website!
I would think that by "unit fractions", they would mean fractions having a numerator of 1.
So, I would separate the given fraction into the following:
11%2F18+=+2%2F18+%2B+3%2F18+%2B+6%2F18
Now replace each of the new fractions with their eqivalent fractions by simplifying each one of them.
2%2F18+=+1%2F9
3%2F18+=+1%2F6
6%2F18+=+1%2F3
The three unit fractions are:
1%2F9, 1%2F6, 1%2F3



Polynomials-and-rational-expressions/6622: How do I simplify %28%28x%5E2-2x-15%29%2F%28%28x-6%29%28x-3%29%29%29%2A%28%282x-6%29%2F%28x-5%29%29
1 solutions

Answer 3621 by Earlsdon(6294) About Me  on 2005-08-04 22:54:09 (Show Source):
You can put this solution on YOUR website!
Try this:
%28%28x%5E2-2x-15%29%2F%28%28x-6%29%28x-3%29%29%29%2A%28%282x-6%29%2F%28x-5%29%29
Factor the numerator of the 1st fraction.
%28%28%28x%2B3%29%28x-5%29%29%2F%28%28x-6%29%28x-3%29%29%29%2A%28%282x-6%29%2F%28x-5%29%29
Now factor 2 from the numerator of the 2nd fraction.
%28%28%28x%2B3%29%28x-5%29%29%2F%28%28x-6%29%28x-3%29%29%29%2A%282%28x-3%29%2F%28x-5%29%29
After cancelling like factors in top and bottom you are left with:
%282%28x%2B3%29%29%2F%28x-6%29
Does this help?


Quadratic_Equations/6637: I checked all of your solvers for quadratic functions, but did not understand what one of my questions was asking...the question was:
Solve the equation by completing the square. Leave irrational roots in simplest
radical form. x^2+4x-12=0
On your solvers, i typed in my equation, and it worked, but i didn't know what my question was asking for, so the answers didn't do me any good. Could you please help me with my question? Thank you!!
1 solutions

Answer 3616 by Earlsdon(6294) About Me  on 2005-08-04 22:20:06 (Show Source):
You can put this solution on YOUR website!
One of the methods of solving quadratic equations is known as "completing the square".
This method entails making a perfect square trinomial from the given quadratic equation or expression, then factoring the perfect square trinomial into its two identical factors.
This is best demonstrated by illustration:
Starting with your quadratic equation:
x%5E2+%2B+4x+-+12+=+0
1) Move the constant to the right side of the equation, i.e. add 12 to both sides.
x%5E2+%2B+4x+=+12
2) Add a new constant that is the square of one-half of the x-coefficient.
%28%281%2F2%29%284%29%29%5E2+=+4 to both sides.
x%5E2+%2B+4x+%2B+4+=+16
3) Factor the trinomial.
%28x+%2B+2%29%28x+%2B+2%29+=+16 or
%28x+%2B+2%29%5E2+=+16
Now take the square root of both sides.
sqrt%28%28x+%2B+2%29%5E2%29+=+%28%2B-+sqrt%2816%29%29
x + 2 = +/-4 Subtract 2 from both sides.
x = 4 - 2 = 2 or
x = -4 -2 = -6
In this case the roots are real.


Polynomials-and-rational-expressions/6640: I know that this doesn't go in this section of questions, but there wasn't a sectioin for trinomials...So if you can, please help me on this question..
Find the value of c that makes each trinomial a perfect square.
x^2+4x+c
I'm not sure how to do this...its quite confusing. Thanks for helping me.
1 solutions

Answer 3609 by Earlsdon(6294) About Me  on 2005-08-04 21:50:31 (Show Source):
You can put this solution on YOUR website!
To find the value of c that makes x%5E2+%2B+4x+%2B+c a perfect square, just take the coefficient of the x-term (4), divide it by 2 and then square the result.
%284%2F2%29%5E2+=+4
So, the trinomial becomes: x%5E2+%2B+4x+%2B+4
Now this factors into: %28x+%2B+2%29%28x+%2B+2%29 or %28x+%2B+2%29%5E2


Geometric_formulas/6624: Solce C=2(pi)r for r
1 solutions

Answer 3603 by Earlsdon(6294) About Me  on 2005-08-04 18:30:10 (Show Source):
You can put this solution on YOUR website!
Solve: C+=+2%28pi%29r for r.
Simply divide both sides by 2(pi)
C%2F2%28pi%29=+r


Quadratic-relations-and-conic-sections/6588: How do I figure out whether or not the vertex of +y=+-99%28x-7%29%5E2+-+2+ is a minimum value? Any sort of help with this problem would be appreciated.
1 solutions

Answer 3586 by Earlsdon(6294) About Me  on 2005-08-04 13:32:19 (Show Source):
You can put this solution on YOUR website!
Take a look at the coefficient of the x^2 term. Notice that it is negative: This indicates that the parabola opens downward, therefore, the vertex must be a maximum.
The equation is in the form:
y+=+a%28x-h%29%5E2+%2B+k
The vertex is located at (h, k) or at ( 7, -2)


Geometric_formulas/6547: I need to find the radius of a circle with only the circumference(6.8m)and i've read the other answers you've given others but I don't get it
1 solutions

Answer 3543 by Earlsdon(6294) About Me  on 2005-08-03 20:25:49 (Show Source):
You can put this solution on YOUR website!
You can find the radius of a circle when you know its circumference because:
C = 2(pi)r or
The circumference (C) is equal to two times pi (pi = 3.14) times the radius (r).
Rewrite this equation for r: r = C/2pi
2pi is aproximately 2(3.14) = 6.28
C = 6.8 meters.
So, r = 2(3.14)(6.8 meters) = 42.7 meters.
The radius is 42.7 meters, approximately.


Linear-systems/6471: Hi there,
I am confronted with the following question:
"A job takes 4 hrs for two people working together. If one person works alone he can do the job in 6 hrs. How long will it take the other person working alone to complete the job?"
I don't really know how to approach this question. It seems so simple yet I can't seem to figure out why the answer is 12 hrs. Please help me out.
Thanks in advance,
Mike
1 solutions

Answer 3472 by Earlsdon(6294) About Me  on 2005-08-02 18:48:26 (Show Source):
You can put this solution on YOUR website!
This kind of problem can be solved by asking "how much of the job is done in 1 hour?"
Let's call the two people Sam and Eric, or S and E for short.
So, S and E together can do the whole job in 4 hours. This means that they can do 1/4 of the job in 1 hour.
Now, Sam can do the whole job in 6 hours. This means that Sam can do 1/6 of the job in 1 hour.
To find find out how much of the job Eric can do in 1 hour, simply subtract what Sam can in 1 hour from what Sam & Eric can do together in 1 hour.
(S + E) - S = E
1/4 - 1/6 = 3/12 - 2/12 = 1/12
So, Eric can do 1/12 of the job in 1 hour, which means it will take him 12 hours to do the whole job.


Linear-systems/6381: Find the equation of line which is perpendicular to the line y = x + 1 and passes the point (1,3)
I need HELP!!!!!! Thank you. If possible an immediate response would be greatly appreciated. Thank you again.
1 solutions

Answer 3425 by Earlsdon(6294) About Me  on 2005-08-01 18:33:44 (Show Source):
You can put this solution on YOUR website!
Recall that perpendicular lines have slopes that are the negative reciprocal of each other.
What does this mean?
Well...if you know the slope of a line, then you automatically know the slope of all lines that are perpendicular to it. For example: If the slope of a line is m = (-3/5), then the slope of the perpendicular would be the negative reciprocal of (-3/5) which is +5/3
So, the given line has the slope, m = 1.
How do you know this? The given equation is in the slope-intercept form:
y = mx + b Compare this with:
y = x + 1 and you'll see that m (the slope) is 1.
Now your problem doesn't state which form of the equation is required so you could use the slope-intercept form or the point-slope form.
The point-slope form looks like this: y - y1 = m(x - x1) and this would be easier to write since you have all of the required information at hand and no calculations are necessary. The x1 and y1 are just the x and y values of the given point (1, 3)
Now, what is the slope of the new line? It's just the negative reciprocal of 1 which is -1.
Now we can write the equation of the line (in the point-slope form) that is perpendicular to given line (y = x + 1) and which passes through the given point (1, 3).
y - 3 = -1(x - 1)