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Matrices-and-determiminant/731134: How do I find the reduced row echelon?
X + y+ z=3
2x - y + z=2
4x – 2y +3z=5
1 solutions
Answer 447002 by MathLover1(6622) on 2013-03-27 12:17:29 (Show Source):
You can put this solution on YOUR website!your matrix is:
Row operation
1:
 ....add  times the 1st row to the 2nd row =>
Row operation
2:
 .........add  times the 1st row to the 3rd row...=>
Row operation
3:
 ..............multiply the 2nd row by  ...=>..  .
Row operation
4:
 ....add  times the 2nd row to the 3rd row..=>...
Row operation
5:
 ...........add  times the 3rd row to the 2nd row...=>...
Row operation
6:
 .....add  times the 3rd row to the 1st row...>...
Row operation
7:
 ....add  times the 2nd row to the 1st row...=>...
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Finance/731111: Which of the following is true of the roots of the equations x^2-6x+8=0?/p> A. They are opposite in sign and equal. B. They are opposite in sign and the larger 1 solutions
Answer 446996 by MathLover1(6622) on 2013-03-27 11:24:47 (Show Source):
You can put this solution on YOUR website!
 ...first factor completely (or use quadratic formula) to find roots
 .....write  as
 ........group
roots:
if  ...=>..
if  ...=>..
so, your answer is: They are both positive.
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test/730942: Let P(-3,6) and Q(10,1) be two points in the coordinate plane
Find an equation of the circle that contains P and Q and whose center is the midpoint of the segment PQ 1 solutions
Answer 446942 by MathLover1(6622) on 2013-03-26 21:41:29 (Show Source):
You can put this solution on YOUR website!The standard equation of a circle with center C(  ,  ) and radius  is as follows:
so, we need to find  ,  , and
since the circle that contains P and Q , the distance between them is equal to diameter of the circle:
| Solved by pluggable solver: Distance Formula |
The first point is (x1,y1). The second point is (x2,y2)
Since the first point is (-3, 6), we can say (x1, y1) = (-3, 6)
So , 
Since the second point is (10, 1), we can also say (x2, y2) = (10, 1)
So , 
Put this all together to get: , , , and 
--------------------------------------------------------------------------------------------
Now use the distance formula to find the distance between the two points (-3, 6) and (10, 1)

Plug in , , , and 




==========================================================
Answer:
The distance between the two points (-3, 6) and (10, 1) is exactly units
The approximate distance between the two points is about 13.9283882771841 units
So again,
Exact Distance: units
Approximate Distance: units
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so, diameter  ...=>...  ...=>...
now find midpoint:
| Solved by pluggable solver: Midpoint |
The first point is (x1,y1). The second point is (x2,y2)
Since the first point is (-3, 6), we can say (x1, y1) = (-3, 6)
So , 
Since the second point is (10, 1), we can also say (x2, y2) = (10, 1)
So , 
Put this all together to get: , , , and 
----------------------------------------------------------------------------------------
Finding the x coordinate of the midpoint: Add up the corresponding x coordinates x1 and x2 and divide that sum by 2
X Coordinate of Midpoint = 
X Coordinate of Midpoint = 
X Coordinate of Midpoint = 
X Coordinate of Midpoint = 
So the x coordinate of the midpoint is 3.5
----------------------------------------------------------------------------------------
Finding the y coordinate of the midpoint: Add up the corresponding y coordinates y1 and y2 and divide that sum by 2
Y Coordinate of Midpoint = 
Y Coordinate of Midpoint = 
Y Coordinate of Midpoint = 
Y Coordinate of Midpoint = 
So the y coordinate of the midpoint is 3.5
===============================================================================
Summary:
The midpoint of the segment joining the two points (-3, 6) and (10, 1) is (3.5, 3.5).
So the answer is (3.5, 3.5)
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center is (  ,  )=(  ,  )...so  and
 ...plug in  ,  , and
your equation is:
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Triangles/730645: The sides of a triangle measure 16, 30, and 34. Which type of triangle is it? 1 solutions
Answer 446775 by MathLover1(6622) on 2013-03-26 09:07:01 (Show Source):
You can put this solution on YOUR website!Types of Triangles:
 : The Isosceles triangle shown on the left has two equal sides and two equal angles.
 : The Equilateral triangle shown on the left has three equal sides and three equal angles. Each angle is  °
 : The Scalene Triangle has no congruent sides. In other words, each side must have a different length.
 : The Obtuse Triangle has an obtuse angle (an obtuse angle has more than  °).
 : The Acute Triangle has three acute angles (an acute angle measures less than  °)
 : A right triangle has one  °.
you are given: the sides of a triangle measure  ,  , and
as you can see, all sides are different in length; so, your triangle is NOT an Isosceles nor Equilateral triangle
it could be Scalene (because has no congruent sides), could be Obtuse (might have an obtuse angle),could be Acute (might have an Acute angle), or could be Right Triangle (might have an right angle angle).
let's check first is it Right Triangle because we can do it using Pythagorean theorem:
let's sides  and  be legs, and  hypotenuse
then we have  if this true, we have a Right Triangle
 ...so, this is true and your triangle IS
but, it is also a scalene triangle with a right angle
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Quadratic_Equations/730485: I need help in writing a word problem involving a quadratic function. And I need to explain it in terms someone not in class could understand it, please. I am in the home stretch of my class and would really appreciate the help. Thank you 1 solutions
Answer 446691 by MathLover1(6622) on 2013-03-25 19:47:19 (Show Source):
You can put this solution on YOUR website!
A function  is a quadratic function if  where  ,  , and  are real numbers and not equal to  .
The graph of a quadratic function is a  . The most basic aid in graphing a parabola is knowing whether  (the graph opens  ) or  (the graph opens  ).
The two simplest quadratic functions are  and  .
a word problem involving a quadratic function:
An inquiry shows that  students will attend a theater play in one week if the ticket price is  dollars. Suppose that for every  dollars added to the ticket price,  fewer students will attend the play.
1. What ticket price will give the  for the week?
2. what is the approximate  for the week if the theater play spends approximately  million dollars to have the play showed for one week?
answer:
1. Let  be the number of times $  is added to the ticket price (and  fewer students attend).
Revenue for the week is
=
=
=
Thus the greatest revenue is given by the maximum of function  . It is a quadratic function with a maximum of  where  is the value of  for which the revenue will be greatest.
To answer the question, calculate the corresponding ticket price by adding $  to the original $  .
2.
Since spendings are fixed, maximum profit is obtained when maximum revenue is obtained as above, for  .
=$
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Complex_Numbers/730436: IF 1000 YEARS EQUAL A 24 HOUR DAY HOW MUCH WOULD 1 SECOND EQUAL PLESE HELP ME 1 solutions
Answer 446683 by MathLover1(6622) on 2013-03-25 19:04:01 (Show Source):
You can put this solution on YOUR website!
so, in  you will have
But if you want to find out an exact number you must do some research, I might be wrong here, but a year with 1 extra day occurs once every 4th year, so:
1000/4 = 250 this is 250 years with 1 extra day, which changes the math into making us take into account that 250 years of those 1000 has 366 days instead of 365
Or, you can forget leap years and use a more sane representation of years such Julian years (  days, exactly) or tropical years (  days at the epoch J2000.0)
so in  years will be  days
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Trigonometry-basics/730327: Write the equation of the circle whose center is (-2,-1) and radius is 2(sqrt[3]) 1 solutions
Answer 446645 by MathLover1(6622) on 2013-03-25 14:18:51 (Show Source):
You can put this solution on YOUR website!Equation of a circle whose center is at (  ,  ) is:
 ....This referrers to the "center-radius form". It may also be referred to as "standard form".
given:
center is at (  ,  ) = (  ,  )
and
plug given values in formula
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Circles/730156: how is the steps done for these?
Find the centre and the radius of
1.)25x^2+25y^2=25
1 solutions
Answer 446513 by MathLover1(6622) on 2013-03-24 23:20:25 (Show Source):
You can put this solution on YOUR website!The  form of the circle equation is in the format  , with the center being at the point (  ,  ) and the radius being "  ".
 ....both sides divide by
 ....compare to  and you see that (  ,  )=(  ,  ) and
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test/730136: Graph the linear equation f(x)=6x 1 solutions
Answer 446511 by MathLover1(6622) on 2013-03-24 23:11:56 (Show Source):
You can put this solution on YOUR website!
| Solved by pluggable solver: Graphing Linear Equations |
In order to graph we only need to plug in two points to draw the line
So lets plug in some points
Plug in x=-1

Multiply
Add
So here's one point (-1,-6)

Now lets find another point
Plug in x=0

Multiply
Add
So here's another point (0,0). Add this to our graph

Now draw a line through these points
So this is the graph of through the points (-1,-6) and (0,0)
So from the graph we can see that the slope is (which tells us that in order to go from point to point we have to start at one point and go up 6 units and to the right 1 units to get to the next point) the y-intercept is (0, )and the x-intercept is ( ,0)
We could graph this equation another way. Since this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0, ).
So we have one point (0, )

Now since the slope is , this means that in order to go from point to point we can use the slope to do so. So starting at (0, ), we can go up 6 units

and to the right 1 units to get to our next point

Now draw a line through those points to graph 
So this is the graph of through the points (0,0) and (1,6)
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Linear-equations/730137: Someone PLEASE HELP me solve this inequality problem !
~ Graph the inequality x + y is Less than or Equal to 4. Give it in interval
notation.
Thank You ! 1 solutions
Answer 446502 by MathLover1(6622) on 2013-03-24 22:17:03 (Show Source):
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Linear-systems/730051: Please HELP me solve this quesion !!!
A line passes through the points (2,9) and (9,2) ~
a. Write the equation of the line.
b. Write the equation of the parallel line going through the origin.
c. Write the equation of the perpendicular line through (2,9). 1 solutions
Answer 446427 by MathLover1(6622) on 2013-03-24 19:17:09 (Show Source):
You can put this solution on YOUR website!
a.
the equation of the line passes through the points (  ,  ) and (  ,  )
| Solved by pluggable solver: FIND EQUATION of straight line given 2 points |
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (2, 9) and (x2, y2) = (9, 2).
Slope a is .
Intercept is found from equation , or . From that,
intercept b is , or .
y=(-1)x + (11)
Your graph:

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b.
the equation of the parallel to line  going through the origin (  ,  )
| Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line |
Since any two parallel lines have the same slope we know the slope of the unknown line is (its from the slope of which is also ).
Also since the unknown line goes through (0,0), we can find the equation by plugging in this info into the point-slope formula
Point-Slope Formula:
where m is the slope and ( , ) is the given point
Plug in , , and 
Distribute 
Multiply
Add to both sides to isolate y
Combine like terms
So the equation of the line that is parallel to and goes through ( , ) is 
So here are the graphs of the equations and 
graph of the given equation (red) and graph of the line (green) that is parallel to the given graph and goes through ( , )
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c.
the equation of the perpendicular to line  through (  ,  )
| Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line |
Remember, any two perpendicular lines are negative reciprocals of each other. So if you're given the slope of , you can find the perpendicular slope by this formula:
where is the perpendicular slope
So plug in the given slope to find the perpendicular slope
When you divide fractions, you multiply the first fraction (which is really ) by the reciprocal of the second
Multiply the fractions.
So the perpendicular slope is 
So now we know the slope of the unknown line is (its the negative reciprocal of from the line ).
Also since the unknown line goes through (2,9), we can find the equation by plugging in this info into the point-slope formula
Point-Slope Formula:
where m is the slope and ( , ) is the given point
Plug in , , and 
Distribute 
Multiply
Add to both sides to isolate y
Combine like terms
So the equation of the line that is perpendicular to and goes through ( , ) is 
So here are the graphs of the equations and 
graph of the given equation (red) and graph of the line (green) that is perpendicular to the given graph and goes through ( , )
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 ...given line
 ...parallel line
 ...perpendicular
let's graph them all together:
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Triangles/730033: What type of triangle has the side lengths of 2,3,4 ?
What type of triangle has the side lengths of 2,3,5 ?
What type of triangle has the side lengths of 6,8,9 ?
What type of triangle has the side lengths of 6,8,10 ? 1 solutions
Answer 446397 by MathLover1(6622) on 2013-03-24 18:20:22 (Show Source):
You can put this solution on YOUR website! By the number of  sides they have:
•  - all  sides have  lengths
•  -  sides have  lengths
•  -  sides are
type of triangle has the side lengths of  ,  ,  is  triangle
type of triangle has the side lengths of  ,  ,  is  triangle
type of triangle has the side lengths of  ,  ,  is  triangle
What type of triangle has the side lengths of  ,  ,  is  triangle
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