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Recent problems solved by 'Earlsdon'
Earlsdon answered: 6281 problems
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Answer 31865 by Earlsdon(6287) on 2006-08-04 18:30:09 (Show Source):
You can put this solution on YOUR website!Solve:
 Multiply both sides by 3 to clear the fraction.
 Subtract y from both sides of the equation.
 Add 6 to both sides.
 Divide both sides by 2
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expressions/48111: Can someone help me with this problem?
I need to simplify the following expression:
6x^2y^3 + 9x^2y^3/3x^2y^2
Thanks,
Sher 1 solutions
Answer 31863 by Earlsdon(6287) on 2006-08-04 18:20:35 (Show Source):
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Equations/48149: Solve the equation for the indicated variable. (Leave ± in your answer, when appropriate.)
for t 1 solutions
Answer 31855 by Earlsdon(6287) on 2006-08-04 17:04:08 (Show Source):
You can put this solution on YOUR website!Solve fot t:
 You can use the quadratic formula or "complete the square" to solve this: Let's use the quadratic formula: 
First put your equation into the standard form:
 Here, a = 1, b = -m, and c = -rm
 It looks complicated but we can simplify it a bit.
 or, if you like:
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Human-and-algebraic-language/48130: Mary has 12 more apples than peaches. If she divides each fruit in half she will have 32 pieces of fruit. how many peaches does Mary have? 1 solutions
Answer 31854 by Earlsdon(6287) on 2006-08-04 16:47:33 (Show Source):
You can put this solution on YOUR website!Let P = number of peaches and A = number of apples. From the problem description, you can write:
A = P+12 and, when Mary divides each fruit in half, she will double the number of pieces of fruit, right?:
2A+2P = 32 Simplift this by dividing both sides by 2.
A+P = 16 Now substitute A = P+12 into this equation to find P, the number of peaches.
(P+12) + P = 16 Simplify this.
2P + 12 = 16 Subtract 12 from both sides.
2P = 4 Divide both sides by 2.
P = 2
Mary has 2 peaches.
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Linear-equations/48142: This question is from textbook Beginning Algebra
section 6.1
Please help: I do not get this
Complete the ordered pairs so that each is a solution for the qiven equation.
3x + 4y=12 (0, ), ( , 3/4), ( ,0),(8/3, ) 1 solutions
Answer 31852 by Earlsdon(6287) on 2006-08-04 16:35:06 (Show Source):
You can put this solution on YOUR website!3x+4y = 12
First ordered pair (x, y) is (0, y) To find the value of y, substitute x = 0 into your equation and solve for y.
3(0)+4y = 12
0+4y = 12 Divide both sides of the equation by 4.
y = 12/4 = 3
The first ordered pair is: (0, 3)
One more:
The second ordered pair (x, y) is (x, 3/4). To find the value of x, substitute y = 3/4 into your equation and solve for x.
3x+4(3/4) = 12 Simplify.
3x+3 = 12 Subtract 3 from both sides.
3x = 9 Now divide both sides by 3.
x = 3
The second ordered pair (x, y) is (3, 3/4)
Use the same technique to find the other ordered pairs
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percentage/48132: please do not count this problem against me because i already entered it but nobody answered me.
25 is what part of 35? 1 solutions
Answer 31849 by Earlsdon(6287) on 2006-08-04 16:24:43 (Show Source):
You can put this solution on YOUR website!Hey...who's counting problems?
25 is what part of 35?
To find the percentage...
25 is 71.43% of 35
To find the fractional answer...
25 is 5/7 of 35
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Functions/48126: I was to rewrite the equation as a function of x and this is what I came up with but I cannot figure out which method is right.
2x - 8y = 48
2x + 8y = 2x+48
8y = 2x + 48
8 8 8
y = 2x + 6
8
f(x) = 2x + 6
8 1 solutions
Answer 31836 by Earlsdon(6287) on 2006-08-04 13:04:43 (Show Source):
You can put this solution on YOUR website!Write:
 as a function of x. What you are really asked to do is to solve the equation for y.
 Add 8y to both sides of the equation.
 Now subtract 48 from both sides.
 Finally, divide both sides by 8.
 Or:
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absolute-value/48125: please help me solve this problem
8-1 5/6
8 minus 1 and 5/6
it kind of slips my mind sometimes when it comes to subtracting fractions 1 solutions
Answer 31835 by Earlsdon(6287) on 2006-08-04 12:56:34 (Show Source):
You can put this solution on YOUR website!8 - 1 5/6
You can do this in two steps.
1) 8 - 1 = 7
2) 7 - 5/6 = 6 1/6
To make the second a little easier to understand, you borrow a 1 from the 7 leaving 6. Now you change the 1 you borrowed into 6/6, because 1 = 6/6. (7 = 6 + 6/6)
So now step 2) looks like this:
6&6/6 - 5/6 = 6&1/6
The answer:
8 - 1&5/6 = 6&1/6
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real-numbers/48021: Solve for x Square root [x-1] =x-7 1 solutions
Answer 31753 by Earlsdon(6287) on 2006-08-02 23:38:28 (Show Source):
You can put this solution on YOUR website!Solve for x:
 First, square both sides of the equation.
 Subtract x from both sides.
 Now add 1 to both sides.
 Factor the right side.
 Apply the zero products principle.
 and/or 
If  then 
If  the
The roots are:
x = 5
x = 10
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Sequences-and-series/47852: I solved this problem but I need somebody to please confirm my answer is right. Thanks.
7
__
\
\ (-1/3)^n = - 547/2187
/
/__
n=0
Sn = ( -1/3)^0 + (-1/3)^1+(-1/3)^2+ (-1/3)^3 +(-1/3)^4+ (-1/3)^5 + (-1/3)^6 +
(-1/3)^7
= 0 + (-1/3) + 1/9 + (-1/27) + 1/81 + (-1/243) + 1/729 + (-1/2187)
= -547/2187 1 solutions
Answer 31643 by Earlsdon(6287) on 2006-08-01 15:40:42 (Show Source):
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Rational-functions/47743: 1. Need help in Determine the point A(x,y), b(0,3) c(1,0), d(7,2) don't understand the "vertices of a Parrallogram"
1 solutions
Answer 31552 by Earlsdon(6287) on 2006-07-31 17:00:53 (Show Source):
You can put this solution on YOUR website!"Vertices" simply means "corners"
First graph the given points b(0, 3), c(1, 0), and d(7, 2), then join the points from b to c to d.
Now where would the fourth point a(x, y) have to go in order to make a parallelogram?
Remember that a parallelogram is a quadrilateral (4-sided figure) whose opposite sides are parallel.
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Expressions-with-variables/47747: factor the algebraic expressions completely.
x^2 – 16x + 63 1 solutions
Answer 31550 by Earlsdon(6287) on 2006-07-31 16:44:06 (Show Source):
You can put this solution on YOUR website!Factor completely:
If this expression can be factored, the factors will have the form:
 where:  and 
Make a list of the possibilities:
Since the sum is negative and the product is positive, both m and n must be negative.
Try: m=-3 and n=-21
m+n = -24 and m*n = 63 No good!
Try: m=-9 and m=-7
m+n = -16 and m*n = 63 This will work!
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Linear-systems/47615: please help!
2/3(x+9) is less than or equal to 1/3(2x+12)
A. X is less than or equal to 6
B. x= all real numbers
C. X has no solution
Thank you! 1 solutions
Answer 31451 by Earlsdon(6287) on 2006-07-29 18:03:52 (Show Source):
You can put this solution on YOUR website! Simplify. Apply the distributive property.
 Subtract  from both sides.
 I don't think so!
Since the variable, x, no longer appears in the solution and the solution is not true, then x has no solution.
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Rational-functions/47449: Solve by completing the square. Other methods will receive no credit.
x2 + 6x + 2 = 0
1 solutions
Answer 31326 by Earlsdon(6287) on 2006-07-27 09:44:30 (Show Source):
You can put this solution on YOUR website!Solve by completing the square.
 First, subtract 2 from both sides of the equation.
 Complete the square on the left side by adding the square of half the x-coefficient  to both sides of the equation.
 Now factor the left side.
 Take the square root of both sides.
 Subtract 3 from both sides.
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Rectangles/47399: Are all rectangles squares? 1 solutions
Answer 31309 by Earlsdon(6287) on 2006-07-26 21:09:53 (Show Source):
You can put this solution on YOUR website!A rectangle is a quadrilateral whose angles are each 90 degrees.
A square is a quadrilateral whose sides are equal, so all squares are rectangangles.
A rectangle may have sides that are not all equal, so not all rectangles are squares.
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Average/47400: Suppose Amanda's quiz average is 86, and these are her grades: 84,88,82,90,92,x, where x is unknown. Can you determine the missing grade? If yes, calculate. If not, why not? 1 solutions
Answer 31308 by Earlsdon(6287) on 2006-07-26 21:03:33 (Show Source):
You can put this solution on YOUR website!To find the average of a set of numbers (grades), add the numbers and divide by the number of numbers (6 in this case). Amanda's average is 86, so:
 simplify and solve for x.
 Multiply both sides of the equation by 6.
 Subtract 436 from both sides.
The missing grade is 80.
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Linear-systems/47402: Hi,
I would really appreciate some help with this question:
A painter can prepare and paint a room in 10 hours. His son requires 18 hours to do the same job. How long will it take to prepare and paint the room working together?
Thank you,
Louis 1 solutions
Answer 31307 by Earlsdon(6287) on 2006-07-26 20:54:55 (Show Source):
You can put this solution on YOUR website!Here's one approach: Find the hourly rates of each person.
If the painter can do the whole job in 10 hours, then he can do 1/10 of the job in 1 hour.
If his son can do the whole job in 18 hours, then he can do 1/18 of the job in 1 hour.
Together, they can do (1/10 + 1/18) of the job in 1 hour.
So together, in 1 hour they can do (9/90 + 5/90 = 14/90) of the job in 1 hour.
This means it will take them 90/14 hour to do the whole job together.
90/14 hour = 6 hrs and 25.7 minutes.
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Expressions-with-variables/47403: Hi,
I would really appreciate some assistance with this problem:
A chemist mixes an 11% acid solution with a 4% acid solution. How many milliliters of each solution must he use to get 700 milliliters of a 6% solution?
Thanks,
Louis 1 solutions
Answer 31306 by Earlsdon(6287) on 2006-07-26 20:46:06 (Show Source):
You can put this solution on YOUR website!Let x = the number of ml of the 11% acid solution. The chemist needs to add this to (700-x) ml of the 4% acid solution to get 700 ml of 6% acid solution.
Write the equation, but first change the percents to their decimal equivalents:
0.11x + 0.04(700-x) = 0.06(700) Simplify and solve for x.
0.11x + 28 - 0.04x = 42 Collect like-terms.
0.07x + 28 = 42 Subtract 28 from both sides of the equation.
0.07x = 14 Divide both sides by 0.07
x = 200
700-x = 500
The chemist needs to mix 200 ml of the 11% acid solution with 500 ml of the 4% acid solution to obtain 700 ml of 6% acid solution.
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Distributive-associative-commutative-properties/47150: This question is from textbook advanced mathematical concepts precalculus with applications
an 18inch by 20 inch sheet of cardboard is cut and folded to make a box for the great pecan company
1.Write a polynomial function to model the volume of the box
2.Graph the function
3.The company wants the box to have a volume of 224 cubic inches.Write an equation to model this situation.
4.Find a positive integer for x. 1 solutions
Answer 31226 by Earlsdon(6287) on 2006-07-24 21:59:53 (Show Source):
You can put this solution on YOUR website!To make a box from a 18 by 20 inch piece of cardboard, you would need to cut the corners from the piece. Let's say that you cut an x by x square from each corner of the given piece of cardboard so that you could then fold the sides up to form an open box. The volume of the resulting box can be expressed by the following polynomial function of x:
 Simplify.
 This is the polynomial function.
The graph looks like this:
If the volume is to equal 224 cubic inches, the equation would be:
 Subtract 224 from both sides.
 Simplify by dividing through by 4.
 Solve for x
The 3 solutions are:
x = 0.73
x = 6.53
x = 11.74
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Permutations/47152: I hope I got this right..can you tell me, please?
What are the number of permutations of the letters of the word MATH?
4, 48, 4! or 4.4.4.4
I chose 48, because 4 x 4 = 16 and 16 x 3 = 48
Thank you !!! 1 solutions
Answer 31221 by Earlsdon(6287) on 2006-07-24 20:53:38 (Show Source):
You can put this solution on YOUR website!You are looking for the number of permutations of 4 things (MATH) taken 4 at-a-time.
 but in this problem, r = n = 4
 (4-4)! = 0! = 1
 = 4*3*2*1 = 24
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real-numbers/47151: Hello, I haven't done any work on this problem because I don't understand the explaination in the book. (Saxon) Can you please help me? Thank you!
Question:
Between which 2 consecutive whole numbers does the square root of 250 lie? The square root sign has a little "5" above it's arm on the left.
1 solutions
Answer 31218 by Earlsdon(6287) on 2006-07-24 20:44:42 (Show Source):
You can put this solution on YOUR website!You are being asked to estimate the value of the fifth root of 250.
So you are looking for the integer, n, which, when raised to the fifth power, is close to 250.
You can do this with a calculator:
So, the fifth root of 250 lies between the fifth root of 243 (3) and the fifth root of 1024 (4). So the fifth root of 250 lies between 3 and 4.
If you are not permitted to use a calculator on this problem, then do the following:
 = 32
 = 243
 = 1024
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percentage/47149: Hello, Can you tell me if I did this right?
15 1/2 percent of 1,200
15.50% or 1,200
n= 15.50% . 1,200 = 186
Thank you!!! 1 solutions
Answer 31217 by Earlsdon(6287) on 2006-07-24 20:31:18 (Show Source):
You can put this solution on YOUR website!While your answer is correct, it isn't clear to me exactly how you arrived at the correct solution.
Think about this: 15.5% of 1,200 Change the percent to a decimal and then multiply by 1,200
15.5% = 0.155
0.155 X 1,200 = 186
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