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funmath answered: 2925 problems
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Answer 40023 by funmath(2925) on 2006-10-27 07:23:20 (Show Source):
You can put this solution on YOUR website!3(2x-3)-6x=10
3(2x)+3(-3)-6x=10
6x-9-6x=10
(6-6)x-9=10
0x-9=10
0-9=10
-9=10
You're not crazy, this problem has no solution. When your variables are eliminated, and the two sides of the equation are not equal, there is no solution.
Happy Calculating!!!
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Linear-equations/58371: Find the slope of the line passing through the points (–8, –3) and (–2, 2). 1 solutions
Answer 39988 by funmath(2925) on 2006-10-26 20:16:37 (Show Source):
You can put this solution on YOUR website!Find the slope of the line passing through the points (–8, –3) and (–2, 2).
The formula for finding the slope when given two points is: 
(x1,y1)=(-8,-3) and (x2,y2)=(-2,2)

Happy Calculating!!!
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Linear-equations/58365: Hi,
I can do this problem by sight; meaning I know what numbers will work by looking at it, I do not know how to do them if I couldn't do it by sight though.
The problem is:
x-2y=4
I did x=4 and y=0.
I know by looking at this that x could equal zero and y could equal a -4.
I do not know how to do the problem other than by figuring out in my head what 2 numbers would leave me with the answer of 4.
I hope you can help me. Thank you.
1 solutions
Answer 39983 by funmath(2925) on 2006-10-26 19:46:16 (Show Source):
You can put this solution on YOUR website!The problem is:
x-2y=4
It's great that you're thinking, but you're thinking too hard. Pick an easy number to deal with and substitute it into the equation and solve for the other variable. There are an infinite number of choices.
:
If x=0, then:
(0)-2y=4
-2y=4
-2y/-2=4/-2
y=-2 The ordered pair (x,y)=(0,-2)
Check: 0-2(-2)=4
4=4
:
If y=0, then:
x-2(0)=4
x-0=4
x=4 The ordered pair is (x,y)=(4,0)
Check: 4-2(0)=4
4=4
:
If x=2, then:
2-2y=4
-2+2-2y=-2+4
-2y=2
-2y/-2=2/-2
y=-1 The ordered pair is (x,y)=(2,-1)
Check: 2-2(-1)=4
2+2=4
4=4
:
You really can pick an infinite number of possibilities. A person could lose a brain cell doing that in their head!!!
Happy Calculating!!!
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Linear-systems/58363: solve the following equations and express the answer as an ordered pair if possible
2x-4y=8
x-2y=4 1 solutions
Answer 39979 by funmath(2925) on 2006-10-26 19:34:30 (Show Source):
You can put this solution on YOUR website!solve the following equations and express the answer as an ordered pair if possible
L1) 2x-4y=8
L2) x-2y=4
Multiply L2 by -2 and add it to L1 in order to eliminate one of the variables.
-2(x-2y=4) --->> -2x+4y=-8
:
2x-4y=8
-2x+4y-8
___________
0x+0y=0
0=0
:
This is a special case, our variables are both eliminated and our constants are =. Graphically, they are the same line and have all points in common.
This means there are an infinite number of solutions. Some teachers and books are happy to get that answer or "all real numbers."
:
Others want you to solve either equation for y and write your answer like this:
x-2y=4
-2y=-x+4
-2y/-2=-x/-2+4/-2
y=(1/2)x-2
The answer is: (x,(1/2)x-2)
You don't have to do this last part unless your teacher or book requires it.
:
Happy Calculating!!!
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Linear_Equations_And_Systems_Word_Problems/58356: I am stumped on how to write the following equation
Ernie has $3.65 in nickels and dimes. He has 13 more nickels than dimes. how many coins does he have?
Help 1 solutions
Answer 39972 by funmath(2925) on 2006-10-26 19:12:01 (Show Source):
You can put this solution on YOUR website!Ernie has $.65 in nickels and dimes. He has 13 more nickels than dimes. how many coins does he have?
:
Let the number of dimes be: x
then the number of nickles is: x+13
Then the amount of money in dimes he has is: .10x
The amount of money in nickles is: .05(x+13)
The total amount of money is: $3.65
:
The problem to solve is:
.10x+.05(x+13)=3.65
.10x+.05x+.65=3.65
.15x+.65=3.65
.15x+.65-.65=3.65-.65
.15x=3.00
.15x/.15=3.00/.15
x=20
The amount of dimes: x=20
The amount of nickles: x+13=20+13=33
The total amount of coins are:20+33=53
:
Check does 20 dimes and 33 nickles = $3.65?
.10(20)+.05(33)=$3.65
2.00+1.65=$3.65
$3.65=$3.65 Cool beans, we're right!!!
Happy Calculating!!!
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Functions/58351: Given y=(x-2)/(x+5) fing the inverse function (switch x&y and solve for Y)
Could someone help me with this one plz 1 solutions
Answer 39967 by funmath(2925) on 2006-10-26 18:59:11 (Show Source):
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Polynomials-and-rational-expressions/58171: Divide 2-7x^2+x^4-2x-x^3 by x+2 1 solutions
Answer 39963 by funmath(2925) on 2006-10-26 18:48:03 (Show Source):
You can put this solution on YOUR website!Divide 2-7x^2+x^4-2x-x^3 by x+2
Put your polynomials in descending order.
 divided by x+2
You didn't specify that I had to use long division which is very difficult to me to illustrate because I don't know all the java commands to allow for spaces and lines. I'm using synthetic division.
Change the sign of 2 in x+2, that's on the outside. Put the coefficients on the inside:
-2|1 -1 -7 -2 2
::|
--------------- Bring down the 1
:: 1
:
-2|1 -1 -7 -2 2
::|0 -2
---------------- Multiply -2 by 1 and put it under -1
:: 1
:
-2|1 -1 -7 -2 2
::|0 -2
----------------- add -1 and -2 and put the answer under them
:: 1 -3
:
-2|1 -1 -7 -2 2
::|0 -2 6 2 0
------------------ Repeat the steps until you have this.
:: 1 -3 -1 0 2
These are the coefficients of your polynomial starting 1 degree less than what you started with. The last number is the remainder.
 r=2
 r=2 Sometimes you write the remainder as the numerator and the divisor as the denominator.

Happy Calculating!!!
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Polynomials-and-rational-expressions/58340: I'm stuck on these two, could anyone help please?
Factor the algebraic expressions completely:
6x^2 - 28x + 16
and
x^4 + 2x^3 - 3x - 6
Thank you very much! 1 solutions
Answer 39953 by funmath(2925) on 2006-10-26 18:23:14 (Show Source):
You can put this solution on YOUR website!Factor the algebraic expressions completely:
There are other method you can use for the first polynomial. I am grouping or using the ac method or using the arch method it's got a lot of names.
 First factor out the GCF, 2.
 2 factors that multiply to give you ac=3*8=24, but add to give you b=-14 are -12 and -2 (-12*-2=24 and -2-12=-14) Replace the middle term with -12x-2x
 Group the first two and last two terms
 Factor out the GCF in each parenthesis.
 Factor out the x-4

:
and
:
You have to facto by grouping.
 Group the first two terms and the last two terms.
 Factor the GCF out of each.
 Factor (x+2) out of each.

:
Happy Calculating!!!
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Linear-equations/58320: How do I find the ordered pairs for this equation 2x+y=10 I am not sure how to start I think I SOLVE X AND THEN Y.aM I CORRECT? 1 solutions
Answer 39949 by funmath(2925) on 2006-10-26 18:00:27 (Show Source):
You can put this solution on YOUR website!These are kind of cool because you get to pick the points to solve for. You get to make this as easy as you can.
:
2x+y=10
Let x=0 and solve for y: (0 is easy!)
2(0)+y=10
0+y=10
y=10 This ordered pair (x,y)=(0,10)
:
Now let's let y=0 and solve for x:
2x+0=10
2x=10
2x/2=10/2
x=5 This ordered pair (x,y)=(5,0)
:
Let x=1 and solve for y: (1 is easy too!)
2(1)+y=10
2+y=10
-2+2+y=10-2
0+y=8
y=8 This ordered pair is (1,8)
:
What easy numbers do you want x to be? There are an infinite number of points to choose, make it as easy as you can on yourself.
Happy Calculating!!!
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Linear-equations/58337: write the equation of each line given the slope and y-intercept.
4. m=3/4;y-intercept=-1
5.m=-4;y-intercept=8
6.m=-1/4;y-intercept=0
write the equation of each line given a point on the line and the slope.
7. (0,7), m=-3 1 solutions
Answer 39948 by funmath(2925) on 2006-10-26 17:50:45 (Show Source):
You can put this solution on YOUR website!The slope-intercept form of a line is  , m=slope, and (0,b)=y-intercept.
write the equation of each line given the slope and y-intercept.
4. m=3/4;y-intercept=-1

:
5.m=-4;y-intercept=8

:
6.m=-1/4;y-intercept=0

:
write the equation of each line given a point on the line and the slope.
7. (0,7), m=-3

:
Just put the parts where they belong in the slope intercept form of a line.
Happy Calculating!!!
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Linear-equations/58314: Determine which two equations represent parallel lines.(a) y = x + 3 (b) y = x – 6 (c) y = 2x + 10 (d) y = 2x – 3 1 solutions
Answer 39947 by funmath(2925) on 2006-10-26 17:45:28 (Show Source):
You can put this solution on YOUR website!Determine which two equations represent parallel lines.(a) y = x + 3 (b) y = x – 6 (c) y = 2x + 10 (d) y = 2x – 3
These equations are in slope intercept form:  , m=slope, and b=y-intercept.
Parallel lines have the same slopes.
(a)y=(1)x+3
(b)y=(1)x-6
(a) and (b) both have a slope of 1 and are parallel.
:
(c) y=(2)x+10
(d y=(2)x-3
(c) and (d) both have a slope of 2 and are parallel.
:
Happy Calculating!!!
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Linear-systems/58323: I am working on systems of linear equations, which I have until now been able to complete by using substitution or elimination methods. Now, however, my homework requires me to solve systems with more than two equations. This problem has three equations, each representing a side of a triangle, and is asking for the three coordinates for the vertices.
I founnd the points at which the first line intersects with the other two (seperately), but do not know how to determine the third vertex.
HERE ARE THE EQUATIONS:
x-y=7
3x-11y=-1
x+y+1=0
AND HERE IS MY WORK THUS FAR:
x-y=7
x=7+y
3(7+y)-11y=-1
21+3y-11y=-1
21-8y=-1
-8y=-22
y=2.75
3x-11(2.75)=-1
3x-30.25=-1
3x=29.25
x=9.75
the point for this vertex is (9.75, 2.75)
7+y+y+1=0
8+2y=0
2y=-8
y=-4
x+-4+1=0
x-3=0
x=3
the point for this vertex is (3,-4)
**so i was able to find these two vertices by substitution method, but do not know how to determine the third one. If any tutor could work on this and send me a solution ASAP, so that I am able to complete the rest of the problems, I would greatly appreciate it!!
With much gratitude and thanks,
A STUDENT 1 solutions
Answer 39945 by funmath(2925) on 2006-10-26 17:34:16 (Show Source):
You can put this solution on YOUR website!Dear A Student,
L1) x-y=7
L2) 3x-11y=-1
L3) x+y+1=0
You found the intersection of L1 and L2 (9.75,2.75)
You found the intersection of L1 and L3 (3,-4)
Now you have to find the intersection of L2 and L3:
3x-11y=-1
x+y+1=0--->x=-y-1
:
3(-y-1)-11y=-1
-3y-3-11y=-1
-14y-3=-1
-14y=2

:

The third vertex is (-6/7,-1/7)
It helps to graph the lines so you can see which lines you need to use for each vertex.
Happy Calculating!!!
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Geometry_Word_Problems/58324: The base of a ladder is 3 feet away from the wall. The top of the ladder is 14 feet from the floor. Find the length of the ladder to the nearest thousandth.
Thanks~
ac 1 solutions
Answer 39940 by funmath(2925) on 2006-10-26 17:07:18 (Show Source):
You can put this solution on YOUR website!Hi ac,
The base of a ladder is 3 feet away from the wall. The top of the ladder is 14 feet from the floor. Find the length of the ladder to the nearest thousandth.
:
The ladder, floor and wall form a right triangle in which the wall and floor are the legs and the ladder is the hypotenuse.
The pythagorean theorem can be used to solve this kind of problem:  c=hypotenuse, a=one leg, and b=other leg.
Let the ladder=c.

Happy Calculating!!!
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Probability-and-statistics/58334: Two dice are rolled. What are the number of ways an 8 can appear from the throw of the dice? 1 solutions
Answer 39929 by funmath(2925) on 2006-10-26 16:45:06 (Show Source):
You can put this solution on YOUR website!Two dice are rolled. What are the number of ways an 8 can appear from the throw of the dice?
A die has 1-6 dots possible.
Below you see the ways you can roll 8 with 2 dice.
(2,6),(3,5),(4,4),(5,3),(6,2)
There are 5 ways to roll an two dice with the sum of 8.
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Linear-equations/58315: Find the slope of the line passing through the points (3, 2) and (3, -3). 1 solutions
Answer 39916 by funmath(2925) on 2006-10-26 13:57:37 (Show Source):
You can put this solution on YOUR website!Find the slope of the line passing through the points (3, 2) and (3, -3).
Notice that both the x's are the same. If you connected the two points, you'd have a vertical line. Vertical lines have undefined slopes.
If you did try to find the slope between these two points using the slope fomula:  With the points (x1,y1)=(3,2) and (x2,y2)=(3,-3), you'd get:
 A 0 in the denominator of a fraction is undefined.
Happy Calculating!!!
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Exponential-and-logarithmic-functions/58309: Exponential Functions
It is known that fourth of all aluminum cans distributed will be recycled each year. A company distributes 1,9000 cans.
The number of cans still in use after time t, in years, is given by the following function.
N(t)=1900(1/4)^t
How many cans are still in use after 5 years?
This is not from a text book, I am taking an on-line class.
I have tried this several times and can not seem to figure it out. 1 solutions
Answer 39911 by funmath(2925) on 2006-10-26 12:46:53 (Show Source):
You can put this solution on YOUR website!Exponential Functions
It is known that fourth of all aluminum cans distributed will be recycled each year. A company distributes 1,9000 cans.
The number of cans still in use after time t, in years, is given by the following function.
N(t)=1900(1/4)^t
N(5)=1900(1/4)^(5)
N(5)=1900(1/1024)
N(5)=1.85546875
You can round it off to whatever your asked for. Please double check the formula you typed in, and the question to be sure I gave you what you really wanted.
Happy Calculating!!!
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Polynomials-and-rational-expressions/58284: f(x)= x(x-6)
State wheather the function is a polynomial function or not. If it is,give its degree. If it is not,tell why not. 1 solutions
Answer 39893 by funmath(2925) on 2006-10-26 09:44:41 (Show Source):
You can put this solution on YOUR website!f(x)= x(x-6)
State wheather the function is a polynomial function or not. If it is,give its degree. If it is not,tell why not.
:
 <---it is a polynomial (it has 2 terms).
 <---it's degree is 2.
Happy Calculating!!!
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Linear-equations/58283: Write the slope of a line parallel to the given line.
-5x + y = 12 1 solutions
Answer 39891 by funmath(2925) on 2006-10-26 09:41:08 (Show Source):
You can put this solution on YOUR website!Write the slope of a line parallel to the given line.
-5x + y = 12
:
Put the equation of the line in slope intercept form:  , m=slope, and b=yintercept.
:
-5x+y=12
5x-5x+y=5x+12
 slope m=5
Parallel lines have equal slopes so any line parallel to this one has a slope of 
Happy Calculating!!!
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Geometry_Word_Problems/58100: The width of a rectangle is 3/4 of its length. If the perimeter of the rectangle is 140 feet, what are the dimensions of the rectangle?
Thank you all for your time! 1 solutions
Answer 39890 by funmath(2925) on 2006-10-26 09:36:19 (Show Source):
You can put this solution on YOUR website!The width of a rectangle is 3/4 of its length. If the perimeter of the rectangle is 140 feet, what are the dimensions of the rectangle?
:
The formula for perimeter of a rectangle is: 
Let the length (L) be:x
Then width (W) is: (3/4)x
Perimeter (P) is: 140 ft
: Plug those values into your formula and solve for x:
140=2(x)+2(3/4)x
140=2x+6/4x
140=2x+3/2x
140=(4/2)x+(3/2)x
140=(7/2)x
2(140)=2(7/2)x
280=7x
280/7=7x/7
40=x
Length: x=40 ft.
Width:(3/4)(40)=3(10)=30 ft.
:
Happy Calculating!!!
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Miscellaneous_Word_Problems/58101: THE RANDOLPHS USED 12 MORE GALLONS OF FUEL OIL IN OCTOBER THAN IN SEPTEMBER AND TWICE AS MUCH OIL IN NOVEMBER AS IN SEPTEMBER. IF THEY USED 132 GALLONS FOR THE THREE MONTHS, HOW MUCH WAS USED DURING EACH MONTH?
THANKS FOR ANY HELP. 1 solutions
Answer 39889 by funmath(2925) on 2006-10-26 09:27:41 (Show Source):
You can put this solution on YOUR website!THE RANDOLPHS USED 12 MORE GALLONS OF FUEL OIL IN OCTOBER THAN IN SEPTEMBER AND TWICE AS MUCH OIL IN NOVEMBER AS IN SEPTEMBER. IF THEY USED 132 GALLONS FOR THE THREE MONTHS, HOW MUCH WAS USED DURING EACH MONTH?
:
Let the amount used in Sept.=x
Then the amount used in Oct.=x+12
Then the amount used in Nov.=2x
Add the months together=132
:
Equation to solve:
(x)+(x+12)+(2x)=132
4x+12=132
4x+12-12=132-12
4x=120
4x/4=120/4
x=30
:
Sept: x=30 gal
Oct:x+12=30+12=42 gal
Nov:2x=2(30)=60 gal
:
Check, if you add all three months do you get 132 gal?
30+42+60=132
132=132 Yes it does!!!
Happy Calculating!!!
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Inequalities/58117: solving inequalities: 5x - 14 < 6 1 solutions
Answer 39887 by funmath(2925) on 2006-10-26 09:17:46 (Show Source):
You can put this solution on YOUR website!solving inequalities:
5x - 14 < 6
5x-14+14<6+14
5x<20

x<4
This is read x is less than 4, if you need to graph this on a number line, put either a o ar a ) over 4 (that depends on your book and teacher) and shade over the numbers that are less than 4.
<<========o--------->
-1,0,1,2,3,4,5,6,7,8,9
Happy Calculating!!!
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Exponents/58280: Let C = 64/27. Then find C with exponent -2/3. 1 solutions
Answer 39886 by funmath(2925) on 2006-10-26 09:01:04 (Show Source):
You can put this solution on YOUR website!Let C = 64/27. Then find C with exponent -2/3.
 Flip the fraction and change the sign of the exponent.
 Notice that 27=3^3 and 64=4^3
 Multiply the inner exponents by the outer exponents.
 Cancel the 3's
 Apply the squares
 Pat yourself on the back your done.
Happy Calculating!!!
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Functions/58238: State the degree of the following polynomial:
8x^3 + 6x^2y + 4xy^3 - 2y^4 1 solutions
Answer 39885 by funmath(2925) on 2006-10-26 08:52:50 (Show Source):
You can put this solution on YOUR website!State the degree of the following polynomial:
8x^3+6x^2y+4xy^3-2y^4
The degree of a polynomial is the degree of it's highest degreed term.
8x^3 <--degree 2
6x^2y <--degree 2+1=3
4xy^3 <--degree 1+3=4
2y^4 <--degree 4
The two highest degreed terms have a degree of 4, so the degree of the polynomial is 
Happy Calculating!!!
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Linear-equations/58241: Parallel to y-1=0 with y-intercept (0,-1) 1 solutions
Answer 39884 by funmath(2925) on 2006-10-26 08:45:53 (Show Source):
You can put this solution on YOUR website!Parallel to y-1=0 with y-intercept (0,-1)
y-1=0
y-1+1=0+1
y=1
This is a special case. Any time you have y=k, where k is a real number and there's no x, you have a horizontal line going through k. In this case y=1 is a horizontal line going through y=1. Horizontal lines have slopes of 0 because y never changes.
A line parallel to a horizontal line would also be parallel. Horizontal lines have the same y value for every point.
The equation of a horizontal line going through (0,-1) is 
Happy Calculating!!!
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