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Earlsdon answered: 6281 problems
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x2 + 8x + 13 = 0
Show in steps please
1 solutions
Answer 15472 by Earlsdon(6287) on 2006-02-24 17:52:04 (Show Source):
You can put this solution on YOUR website!Solve by completing the square:
 Subtract 13 from both sides of the equation.
 Complete the square in the x-terms by adding the square of half the x-coefficient  to both sides.
 Factor the left side.
 Take the square root of both sides.
 = +or-  Finally, subtract 4 from both sides.
 or
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Volume/28462: Question:The volume of a cube is given V=s^3. Find the length of a cube if the volume is 1000 cm^3. i do not know where to start. 1 solutions
Answer 15469 by Earlsdon(6287) on 2006-02-24 12:23:45 (Show Source):
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percentage/28391: I am trying to help my son with his homework but the book does not show an example for the problem we are trying to solve. We are working on percent proportion. The problem is 19.8 is what percent of 36. Can you help me with breaking this problem down so that we might understand how to work it out.
Thank you,
Julie Morehouse 1 solutions
Answer 15422 by Earlsdon(6287) on 2006-02-23 20:39:28 (Show Source):
You can put this solution on YOUR website!Here's one way to tackle problems like this:
x/100 = is#/of#
Explanation:
The x is the percentage you are trying to find.
The is# is taken from the problem, which in your case, it says" ...19.8 is what..." So 19.8 is the is#
The of# is also taken from the problem, which in your case, it says "...what percent of 36." So 36 is the of#.
So we have:
 Now multiply both sides of this equation by 100.
The answer is:
19.8 is 55% 0f 36
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test/28332: An isosceles triangle has two sides that measure 2 inches and one side that measures 3 inches.A similar isosceles triangel has two sides each 8 inches long.What is the length of the third side? 1 solutions
Answer 15408 by Earlsdon(6287) on 2006-02-23 11:02:47 (Show Source):
You can put this solution on YOUR website!The two isosceles triangles are "similar" so their sides are "proportional"
Find the scale factor by dividing the known length of one side of the larger triangle by the known length of a "corresponding" side of the smaller triangle.
Scale factor is: 8"/2" = 4
Multiply the length of the base of the smaller triangle by the scale factor of 4 to find the unknown length of the base of the larger triangle.
Base of smaller triangle = 3"
Base of larger triangle = 4 X 3" = 12"
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Rational-functions/28283: I'm really lost at math. It's been about 19 years and I'm back in college. College algebra has been given to me without taking a refresher course. I am ohhh so lost. I have a 2-part question and would appreciate if someone would show me step by step how to do these.
1)For the equation x-2 sqrt of x = 0, solve for all values of x that satisfies the question.
2)Graph the functions y=x and y=2 sqrt of x on the same graph (by plotting points if necessary). Show the points of intersection of these two graphs.
Thank you so much. 1 solutions
Answer 15405 by Earlsdon(6287) on 2006-02-23 10:49:46 (Show Source):
You can put this solution on YOUR website!1) Solve:
 Subtract  from both sides of the equation.
 Now square both sides.
 Divide both sides by x
2) Here's the graph: The red line is y=x. The green line is 
The points of intersection are: (0,0) and (4, 4)
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percentage/28174: Hello! I homeschool my daughter, and have the answer to this particular problem, but can't figure out how they arrived at the answer. We may end up finding out that I have to call them to tell them that THEIR answer is incorrect. :)))
"A man bought a desk for $125. After spending $75 on repairs, he sold the desk for $350. What was his percent of profit based on the cost?"
The answer in the teacher manual is 120%. Can anyone help me, so that I can better explain to my daughter the steps taken to solve this problem? I tried x over 100 times $150 (profit) = $200 (cost). Help! Thanks! 1 solutions
Answer 15362 by Earlsdon(6287) on 2006-02-22 13:09:02 (Show Source):
You can put this solution on YOUR website!Cost of desk: $125
Selling price: $350 Subtract cost of repairs ($75)
Profit is selling price less cost of repairs less cost of desk.
Profit: ($350 - $75) - $125 = $275 - $125 = $150
Percent profit = (Profit/cost) X 100
Percent profit = ($150/$125)X100 = 120%
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Equations/28176: how do you solve? m^2 + m - 72 = 0 1 solutions
Answer 15360 by Earlsdon(6287) on 2006-02-22 12:52:04 (Show Source):
You can put this solution on YOUR website!Solve: Try factoring.
 The factors will have the form:  where:
a + b = 1 and a*b = -72
Try: a = -8 and b = 9
-8+9 = 1
(-8)(9) = -72
So,
 Factor.
 Apply the zero products principle.
 and/or 
If  then 
If  then
The roots (solutions) are:
x = -8
x = 9
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percentage/28118: If I have 80 apartments and 79 are rented What will be the easyest method to calculate the percentage. I've been multiplyng 79*80%. 1 solutions
Answer 15322 by Earlsdon(6287) on 2006-02-21 21:11:10 (Show Source):
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Quadratic_Equations/28119: Im falling behind in Algebra due to illness. If I could see a problem done for me I could use it as a referance. Any help would be GREATLY appriciated!
Can you please solve the equation by using the "square root method"? Thank you for your time!!! 1 solutions
Answer 15321 by Earlsdon(6287) on 2006-02-21 21:07:12 (Show Source):
You can put this solution on YOUR website!Solve:
 Take the square root of both sides of the equation.
(x-3) = +or- 4 Add 3 to both sides.
x = 3+4 or 3-4
The two roots are:
x = 7
x = -1
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Graphs/28048: can you help me find the equation of the vertical line through (6,5) 1 solutions
Answer 15300 by Earlsdon(6287) on 2006-02-21 11:00:46 (Show Source):
You can put this solution on YOUR website!Think about this! A vertical line has the same x-coordinate wherever you are on the line.
So the equation of a vertical line that passes through the point (6, 5) is just: x = 6
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absolute-value/27999: i am merely a parent try to get the understanding. we have done all the rest. tx.
If a parked car gets to 54 mph in 5 seconds. what is the acceleration?
and lastly
the speed of light is 3 x 10^8 meters per second. how long does it take light to travel the 149 x 10^9 meters distance from the sun to the earth?
tx 1 solutions
Answer 15255 by Earlsdon(6287) on 2006-02-20 21:31:08 (Show Source):
You can put this solution on YOUR website!1) If the car goes from standstill to 54 mph in 5 seconds, you can find the acceleration, assuming it's uniform of course, by dividing the speed (54 mph) by the time (5 secs).
But you must work in similar units, so convert the speed of 54 mph to mps (miles per second) before you divide by the 5 seconds.
54 miles/hour divided by 3600 seconds/hour = 0.015 miles per second.
Now divide 0.015 miles/sec by 5 secs = 0.003 miles/second squared.
This means that the car is increasing its speed at the rate of 0.003 miles for each second of travel.
2) The speed of light,
Distance to sun,
Time of travel, t = distance/speed.
 seconds. Divide this by 60 to get minutes.
t = 8.28 minutes.
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Mixture_Word_Problems/27934: Soybean meal is 16% protein. Corn meal is 10% protein. How much of each type should be mixed to bet a 15-lb mixture that is 12% protein? 1 solutions
Answer 15228 by Earlsdon(6287) on 2006-02-20 16:18:48 (Show Source):
You can put this solution on YOUR website!Let x = the required number of pounds of 16%-protein soybean meal
15-x = the required number of pounds of 10%-protein corn meal.
You want x lbs of 16%-protein (0.16x) plus (15-x) lbs of 0.10%-protein (0.10(15-x)) to equal 15 lbs of 12% (0.12)(15) of mixture.
Change the percents to their eqivalent decimals and write the equation.
 Simplify and solve for x.
 Combine the x-terms.
 Subtract 1.5 from both sides of the equation.
 Divide both sides by 0.06
You will need 5 lbs of 16%-protein soybean meal and 10 lbs of 10%-protein corn meal to make a 15-lb mixture that is 12% protein.
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real-numbers/27914: What does pie mean? 1 solutions
Answer 15224 by Earlsdon(6287) on 2006-02-20 14:19:23 (Show Source):
You can put this solution on YOUR website!Well, the way you have spelled it (pie), it means a delicious baked item, usually circular in shape, whose contents can be any of a variety of delectable fruits.
But seriously...
Pi  is a greek letter that used in mathematics to represent the ratio of the circumference of a circle to its diameter. This ratio is a constant for any circle  . The value of  is an irrational number (a non-repeating, non-terminating decimal) and is commonly approximated by 3.14 or  .
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Miscellaneous_Word_Problems/27920: Please help. Sharon invested money in a savings account at a rate of 6% simple interest. After one year she has $6996 in the account. How much did Sharon originally invest?
Thanks so much. 1 solutions
Answer 15222 by Earlsdon(6287) on 2006-02-20 14:08:41 (Show Source):
You can put this solution on YOUR website!Let x = the amount originally invested. After one year, Sharon will have $x (the original amount) plus 6% of $x (the interest earned on the original amount in one year) and this will equal $6996.00: Change the 6% to its decimal eqivalent.(6% = 0.06) and write the equation.
 Combine the x-terms.
 Divide both sides of the equation by 1.06
Sharon originally invested $6600.00
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Numbers_Word_Problems/27918: I need help please. The perimeter of a triangle is 195mm. If the lengths of the sides are consecutive odd integers, find the length of each side.
Thank you. 1 solutions
Answer 15219 by Earlsdon(6287) on 2006-02-20 13:58:32 (Show Source):
You can put this solution on YOUR website!You can let x = the length of the short side. Then the length of next largest side would be x+2 and the length of the largest side would be x+4. These sides add up to 195 mm. You can set up the equation to find x, the length of the short side.
 Simplify and solve for x.
 Subtract 6 from both sides of the equation.
 Divide both sides by 3.
The length of the short side is 63 mm
The length of the middle side is x+2 = 63+2 = 65 mm
The length of the long side is x+4 = 63 + 4 = 67 mm
Check: 63+65+67 = 195 mm
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Graphs/27841: How would I go about solving a problem such as this? They want me to graph each system of linear equations to find its solution.
x-5y=-30
2x-y=3 1 solutions
Answer 15185 by Earlsdon(6287) on 2006-02-19 22:25:29 (Show Source):
You can put this solution on YOUR website!To graph these, first get the equations into the slope-intercept form: y = mx + b
1)  is 
2)  is
Now you can graph them:

It's a little hard to read from the graph, but the point of intersection (solution) is: (5, 7)
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Radicals/27821: I recently had a quiz at school and one of the problems i missed was 3 on the out side if the radicand sign and then 500 on the inside, may you please tell me how i could go about solving it?
1 solutions
Answer 15166 by Earlsdon(6287) on 2006-02-19 18:07:44 (Show Source):
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Geometric_formulas/27800: A cirlce has its center at the center of the square with 9-inch sides. Find the area of the square not covered by the circle to the nearest 10th.
Is it
a) 2.3 in
b) 8.0 in
c) 17.4 in
d) 64.3 in
I'm not even sure how to figure this out. 1 solutions
Answer 15149 by Earlsdon(6287) on 2006-02-19 11:18:26 (Show Source):
You can put this solution on YOUR website!To find the area inside the square not covered by the circle, you need to find the area of the square then subtract from it the area of the circle.
It is assumed, although you don't say, that the sides of the square are tangent to the circumference of the circle.
The area of the square is found by:  whers S is the length of one side of the square, or 9 inches.
 Square inches.
The area of the circle is found by  and the radius, r, of the circle is equal to half the length of one side of the square, or 4.5 inches. Using 3.14 as an approximation for
 square inches.
Now you will subtract the area of the circle (63.585 square inches) from the area of the square (81 square inches)
81 - 63.585 = 17.415 Rounded to the nearest tenth this is 17.4 square inches.
Answer: 17.4 square inches.
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Radicals/27815: Solve by completing the square.
x^2=5x+2 1 solutions
Answer 15148 by Earlsdon(6287) on 2006-02-19 11:01:26 (Show Source):
You can put this solution on YOUR website!Solve by completing the square:
 First, subtract 5x from both sides of the equation.
 Complete the square in the x-terms by adding the square of half the x-coefficient (that's  to both sides of the equation.
 Simplify.
 Now take the square root of both sides.
 ...and , of course, the right side has a + or - in front. Now add 5/2 to both sides.
 +or-
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Polynomials-and-rational-expressions/27810: I would really appreciate any help you could can give me regarding the two following problems. The instructions are to Factor the polynomial. I have been able to do the others, but for some reason these two have me stuck.
Factor Completely
Problem One - 64-(r+2t)^2
Problem Two - -k^2-h^2+2kh+4
Thanks in advance for your assistance
1 solutions
Answer 15146 by Earlsdon(6287) on 2006-02-19 10:21:38 (Show Source):
You can put this solution on YOUR website!1) Factor:
 You should recognise this as the difference of two squares:  and 
The difference of two squares can be factored:
 Appplying this to your problem:
 =
2) Factor:
 If you rearrange this expression, you will see that it is really the difference of two squares.
 Factor the parentheses.
 Now it's in the form of:  which will factor nicely.
 =
You can verify these answers by multiplying the factors to see that you get back the original expressions.
I'll leave this as an exercise for the student!
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Numeric_Fractions/27813: Miko's class follow the stock market reports for the xyz company. in one week xyz's stock price changed by -2 1/8 points. the following week, the stock price changed by another -1 3/4 points. how many points did the stock drop in this time period? 1 solutions
Answer 15144 by Earlsdon(6287) on 2006-02-19 10:05:41 (Show Source):
You can put this solution on YOUR website!To find the toatal change in xyz's stock price, you will need to add (-2 1/8) and (-1 3/4).
-2 1/8 + (-1 3/4) = -2 1/8 + (-1 6/8) = -3 7/8
The stock price dropped a total of 3 7/8 points.
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Numbers_Word_Problems/27769: The sum of two numbers is 12. Three times the product of the number is 105. What are the numbers?
1 solutions
Answer 15124 by Earlsdon(6287) on 2006-02-18 18:59:36 (Show Source):
You can put this solution on YOUR website!Let the two numbers be a and b.
You can write two equations from the problem description.
 Solve this one for a and substitute into the second equation.
 Simplify and solve for b.
 Subtract 105 from both sides of the equation.
 Multiply through by -1.
 Factor out a 3.
 Apply the zero products principle.
 Factor this quadratic equation.
 Apply the zero products principle again.
 and/or 
If  then 
If  then
The two numbers are: 5 and 7
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