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Parallelograms/244194: The points A(0,0), B(2,4)and D(7,O) are three of the four vertices of a parallelogram. What are the coordinates of the fourth?
The coordinates of three vertices of a square are A(2,-3), B(-2,-1) and C(0,3). What are coordinates of the fourth vertex 1 solutions
Answer 178715 by solver91311(16868) on 2009-11-30 18:30:17 (Show Source):
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Graphs/244160: Okay don't get confused this is suppost to be a data table but I don't know how to do it on this program!!!
Directions: Does the data in the table below show direct variation? Explain.
x_-2_-1_0_1_2
y_-5_-2_1_4_7
Hope that makes sence!!!! 1 solutions
Answer 178704 by solver91311(16868) on 2009-11-30 18:05:55 (Show Source):
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Percentage-and-ratio-word-problems/244123: Here is the problem that I am having trouble explaining to my son.
Scott and Dan are traveling together. First Scott drives one fifth of the way. Then Dan drives one third of the remaining distance. Next Scott drives one half of the remaining distance, and finally Dan drives the last 80 miles. What is the total distance traveled? How far does each person drive.
I know the answer is 300 miles total drive. Scott drove 140 and Dan drove 160.
I don't know how to explain the answer.
Can you help? 1 solutions
Answer 178687 by solver91311(16868) on 2009-11-30 17:22:28 (Show Source):
You can put this solution on YOUR website!
The first thing I have to say is that there is absolutely nothing wrong with the way Alan did this problem. I'm going to look at it from a slightly different direction, then you can choose the one you understand the best.
If Dan drove the final 80 miles, and that was what was left over after Scott had driven half of the remaining distance, then Scott must have driven 80 miles. Score: Dan 80, Scott 80, Total 160.
If Dan drove one-third of the remaining distance and left 160 miles to go, 160 must have been two-thirds of what remained when Dan started, so if 160 is two-thirds, 80 must be one-third, which is the amount Dan drove that leg. Score:
Dan 160, Scott 80, Total 240.
Next, if Scott drove one-fifth of the total trip and left 240 miles to go, then 240 miles must be four-fifths of the total trip. Dividing 240 by 4 gives 60 which is then one-fifth of the total trip and is what Scott drove at the start. Final Score: Dan 160, Scott 140, Total 300.
John

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Trigonometry-basics/244126: please help me to solve this quadratic equation:
Give the propeties for the equation x^2+y^2+8x-2y+15=0, center:
here are the possible answers:
a)(4,1)
b)(-4,1)
c)(-8,2) 1 solutions
Answer 178683 by solver91311(16868) on 2009-11-30 17:07:56 (Show Source):
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Graphs/244092: Find the equation for each of the following items below:
a. A line that passes through (6,2) and has a slope of 2.
b. A line that passes though the points (2,4) and (8,16)
c. A line that passes through (7,3) and has a slope of -1.
d. A line that passes through (1, 1) and is perpendicular to the line 3x+4Y=12.
e. A circle with a radius of 9 and a midpoint at (3,3)
1 solutions
Answer 178671 by solver91311(16868) on 2009-11-30 16:45:04 (Show Source):
You can put this solution on YOUR website!
First thing: You cannot find (or write) "the" equation of a line. There are an infinity of equivalent representations of any line, hence the best you can do is find "an" equation of a line.
If you are given a point and the slope, then use the point-slope form of a line:
Where is the given slope and is the given point.
If you are not given the slope directly, but are given that the desired line is either parallel or perpendicular to a given line, use one of the following to determine the slope:
If you are given two points, you can either compute the slope using the slope formula,
Where and are the coordinates of the given points
And then use the point-slope form as above, or you can use the two-point form of a line:
Which is really nothing more than a combination of computing the slope and writing the equation.
In all cases, you should determine, either from the instructions in your text or from your instructor's guidance, what form your answers should take. Generally, it is one of two forms that are specified, if any:
1. Slope-intercept form: where is the slope and is the point of intersection of the line with the -axis.
2. Standard form: Some text require , , and to be integers for proper standard form.
A circle centered at and with radius is described by:
Since you were given the center and a point on the circle, you will have to calculate the radius by using the distance formula to determine the distance from the center to the given point.
Again where and are the coordinates of the given points.
John

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Radicals/244077: Trying to assist 13 yr old son..
Just when I think there wont be a problem helping him cause he says it's LCD'S mom. I look at the problem and it involves fractions and LCD'S, these I do not know how to do. Any help much appreciated..
What I am looking for is the LCD between the two fractions on questions 1 and 2
1. 5/x-6,7/x^2-12x+36
2.5/7ab^5,2/7a^3b^3
Can anyone help me with these problems? Ihad previously posted this but did not clarify what it was I was looking to find. Sorry 1 solutions
Answer 178662 by solver91311(16868) on 2009-11-30 15:57:51 (Show Source):
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Travel_Word_Problems/244059: I hope you can help
A car travels 180 miles. A second car, traveling 15 m/h faster than the first car, makes the same trip in 1 hour less time. Find the speed of each car. 1 solutions
Answer 178658 by solver91311(16868) on 2009-11-30 15:26:40 (Show Source):
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real-numbers/243988: prove cube root 6 is irrational 1 solutions
Answer 178619 by solver91311(16868) on 2009-11-30 12:03:24 (Show Source):
You can put this solution on YOUR website!
Prove is irrational.
Assume is rational. That means where is reduced to lowest terms, that is and have no common integer factors.
It follows then that:
Since at least one factor of the RHS is even, the entire RHS must be even. Since the RHS is even, the LHS must therefore also be even. Since the product of two odd numbers is always odd, it follows that:
Since is even, it follows that
So:
Now, since at least one factor of the LHS is even, the LHS must be even. Therefore the RHS must be even and must be even. But if is even, then must be even.
Since the the original assumption leads to the conclusion that both and are even, contradicting the part of the original assumption that and have no common integer factors, the assumption that is rational must be false.
Therefore is irrational. QED.
John

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Angles/243985: In any triangle, the sum of the measures of the angles is 180° . In ΔABC, ∢ A is three
times as large as ∢ B and also 16° larger than ∢ C. Find the measure of each angle. 1 solutions
Answer 178613 by solver91311(16868) on 2009-11-30 11:34:13 (Show Source):
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Quadratic_Equations/243867: I am suppose to find out if this equations S= -0.0643t^2 + 3.2152t + 23.9801 is a good equation to base off a companies salary.
I figured it wasn't because it happens to be a parabole that goes down after 25 years of experience. I thought of tbe possibility of people staying at a job for 25 years is highly unlikely but possible... so I figured 18yrs + 25yrs = 43 years of age.
So I figured lowering a employees salary at the age of 44 and on was unethical.
Plus the pay rate increase beforehand was just way to fast and high...
What would you suggest would be a good solution for this company to pay salaries in a equation. It doesn't have to be a quadratic equation but I must be able to graph it.
1 solutions
Answer 178593 by solver91311(16868) on 2009-11-30 03:07:12 (Show Source):
You can put this solution on YOUR website!
In general, I agree with your analysis. Actually, lowering people's salary based solely on their age is more than unethical, it is illegal.
My personal experience has been that I've seen about a 5% increase per year since 1988 -- but that is not necessarily typical.
If you had to write a formula for a company, you would first have to define job categories and pick a base starting salary for each, call that . Then you would have to select a percentage rate, , of increase for each one. Then for job class number 1 current salary, , you could write:
Where is the number of years of employment.
So if the starting salary were say $50K and the rate of increase were 4%, then a graph of:
Would look like the red line and
Would look like the green line
John

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logarithm/242767: just wanna see how these problems are worked out.
1.logc 3sq root y^3 z^2/x^4. sorry could make the sq root sign.
2.1/2loga-log2
3.ln2x-3(lnx-lny) 1 solutions
Answer 177732 by solver91311(16868) on 2009-11-25 16:40:31 (Show Source):
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Mixture_Word_Problems/242727: Babbitt metal is an alloy made up of 90% tin, 7% antimony, 3% copper. How many pounds of pure copper must be added to 150 pounds of the alloy so that it will contain 17% copper? 1 solutions
Answer 177724 by solver91311(16868) on 2009-11-25 16:10:51 (Show Source):
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Miscellaneous_Word_Problems/242766: THE NUMBER OF TAXI ACCIDENTS IS APPROXIMATED BY:
y = -143.3x^2+1823.3x+6820
and the number of injuries is approximated by:
y = -416.72x^2+4416.7x+8500
ACCORDING TO THE EQUATION FOR THE NUMBER OF ACCIDENTS, IF THE TREND CONTINUED, HOW MANY TAXI ACCIDENTS OCCURRED IN 1998?
USE EQUATION FOR THE NUMBER OF INJURIES TO APPROXIMATE THE NUMBER OF PEOPLE INJURED IN 1998.
X=0 REPRESENTS 1990 X=1 REPRESENTS 1991 AND SO ON.
1990 = 6820
1993 = 11,000
1996 = 12,601 1 solutions
Answer 177721 by solver91311(16868) on 2009-11-25 15:59:28 (Show Source):
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