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Functions/366482: f(x)=x/4x-7
1 solutions

Answer 261193 by Fombitz(13828) on 2010-11-05 11:31:15 (Show Source):

You can put this solution on YOUR website!
graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C0%2Cx%2F%284x-7%29%29

Matrices-and-determiminant/366526: what is the awnser for 3x-3y=21
2x-2y=10
1 solutions

Answer 261191 by Fombitz(13828) on 2010-11-05 11:24:20 (Show Source):

You can put this solution on YOUR website!
[A]= %28matrix%282%2C2%2C3%2C-3%2C2%2C-2%29%29

[x]=

[b]=

.
.
.
The determinant of [A] is zero.
The two lines are parallel, there is no solution.
.
.
.
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C0%2C%283x-21%29%2F3%2C%282x-10%29%2F2%29

graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C0%2C%283x-21%29%2F3%2C%282x-10%29%2F2%29

Equations/366528: what number should be added to complete the square of the expression x^2-6x?
1 solutions

Answer 261190 by Fombitz(13828) on 2010-11-05 11:20:48 (Show Source):

You can put this solution on YOUR website!
(1/2) of the x-coefficient, squared.
N=%28%281%2F2%29%28-6%29%29%5E2=%28-3%29%5E2=highlight%289%29

.
.
.

Miscellaneous_Word_Problems/366524: what two numbers when added together equal -15 but multiplied together equal 225?
1 solutions

Answer 261189 by Fombitz(13828) on 2010-11-05 11:19:44 (Show Source):

You can put this solution on YOUR website!
1. A%2BB=-15

From eq. 2,
A=225%2FB

Substitute into eq. 1,
225%2FB%2BB=-15

Use the quadratic formula,
B+=+%28-15+%2B-+sqrt%28+15%5E2-4%2A1%2A225+%29%29%2F%282%2A1%29+

B+=+%28-15+%2B-+sqrt%28+225-900+%29%29%2F%282%29+

B+=+%28-15+%2B-+sqrt%28+-675+%29%29%2F%282%29+

B+=+%28-15+%2B-+15sqrt%28+3%29i%29%2F%282%29+

B+=+%2815%2F2%29%28-1+%2B-sqrt%28+3%29i%29+

Then using eq. 1,
A=%2815%2F2%29%28-1+%2B-sqrt%28+3%29i%29+

So the two numbers are,
highlight%28A=%2815%2F2%29%28-1%2Bsqrt%283%29i%29%29

highlight%28B=%2815%2F2%29%28-1-sqrt%283%29i%29%29

and

highlight_green%28A=%2815%2F2%29%28-1-sqrt%283%29i%29%29

highlight_green%28B=%2815%2F2%29%28-1%2Bsqrt%283%29i%29%29

Expressions-with-variables/366484: 8,-16,-12,-3
y-8>2y-4
is 8 a solution
is -16 a solution
is-12 a solution
is -3 a solution
1 solutions

Answer 261188 by Fombitz(13828) on 2010-11-05 11:11:29 (Show Source):

You can put this solution on YOUR website!
Substitute for

and find out.
I'll do one, you do the rest.
y=8

.
.
.
False, so it's not a solution.

Complex_Numbers/366511: IN THE RIGHT TRIANGLE FIND THE LENGTH OF THE SIDE NOT GIVEN USE A CALCULATOR TO FIND AN APPROXIMATION TO THE DECIMAL PLACES.
A=3 B=5
THE VALUE OF C IS
(ROUND TO NEAREST THOUSANDTH)
1 solutions

Answer 261187 by Fombitz(13828) on 2010-11-05 11:09:38 (Show Source):

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A%5E2%2BB%5E2=C%5E2

Use a calculator to get the appropriate decimal places.

Quadratic_Equations/366485: A parabola with an equation of the form y = ax^2 + bx + c has the point (-2, 1) as its vertex. If (-4, 5) also lies on the parabola, which of the following is
another point on this parabola?
(A) (-4, 3) (B) (-1, 3) (C) (0, 5) (D) (2, 1) (E) (4, 5)
1 solutions

Answer 261186 by Fombitz(13828) on 2010-11-05 11:08:06 (Show Source):

You can put this solution on YOUR website!
Since the vertex occurs at (

), the line of symmetry is x=-2

.
Since (

) is a point on the line, find the x value equidistant from the line of symmetry.
The x-distance from (

) to the line of symmetry is d%5Bx%5D=-2-%28-4%29=2

.
Then add d%5Bx%5D=2

to the x position of the line of symmetry x position to get the point symmetric to (

.
.
(

) is another point on the parabola.
.
.
.

Sequences-and-series/366489: If 3, 6, 12, 2y + 6 is a geometric sequence, what is the value of y?
1 solutions

Answer 261185 by Fombitz(13828) on 2010-11-05 11:00:50 (Show Source):

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Look at the differences between terms,
6-3=3

The next difference should be

Expressions-with-variables/366472: 5/2x+1/4x=9/4+x
1 solutions

Answer 261184 by Fombitz(13828) on 2010-11-05 10:58:30 (Show Source):

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5%2F%282x%29%2B1%2F%284x%29=9%2F%284%2Bx%29

10%2F%284x%29%2B1%2F%284x%29=9%2F%284%2Bx%29

Expressions-with-variables/366470: g(x)=6/7-8x

1 solutions

Answer 261183 by Fombitz(13828) on 2010-11-05 10:55:43 (Show Source):

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graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C6%2F%287-8x%29%29

Numeric_Fractions/366429: subtract -2.3 - -8.8
please help me out
1 solutions

Answer 261178 by Fombitz(13828) on 2010-11-05 10:43:45 (Show Source):

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-2.3+-+%28-8.8%29=-2.3%2B8.8=8.8-2.3=6.5

Graphs/366497: 7x + -2y = 14
1 solutions

Answer 261176 by Fombitz(13828) on 2010-11-05 10:41:16 (Show Source):

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7x-2y+=+14

.
.
.

graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C%287%2F2%29x-7%29

Equations/366500: Given the equation y = 4x + 4, predict the 100th term.

1 solutions

Answer 261174 by Fombitz(13828) on 2010-11-05 10:40:03 (Show Source):

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100th term?
How do you mean?
You have an equation for a straight line.
.
.
.
graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C0%2C4x%2B4%29

graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C0%2C4x%2B4%29

Numeric_Fractions/366514: I am taking classes with the University of Phoenix and this semester I have algebra. The problems is. -2/7x=6/35. I know that you need to multiply both sides by -7/2, and I know that the answer should be -42/70, but they want me to simplify the answer and I just don't undersand where this magical number is supposed to come from. Help!!!!
1 solutions

Answer 261173 by Fombitz(13828) on 2010-11-05 10:38:43 (Show Source):

You can put this solution on YOUR website!

and

both have

and

as factors which means you can simplify.
.
.
.
%28-2%2F7%29x=6%2F35

x=-%287%2F2%29%28%282%2A3%29%2F%285%2A7%29%29

x=-%28cross%287%29%2Fcross%282%29%29%28%28cross%282%29%2A3%29%2F%285%2Across%287%29%29%29

Probability-and-statistics/366399: Hello, Can someone please tell me if my answer is right. Plus I do not know how to interpret their meanings. Please help me I been out of school 15 years.
Thank you so much.
Problem: The number of dry cleaning orders picked up at Sunny Fresh Dry Cleaners was sampled over 8 hour periods. Below is the sample:
150 164 124 98 178 164 79 126 171 164
97 133 164 124 150 111 171 93
From this data set, compute the sample mean, median, mode and midrange. Compute the 1st
quartile and 3rd and interpret their meanings.
ANSWER:
79
93
97
98
111
124
124
126
133
150
150
164
164
164
164
171
171
178
2461
Mean = 2461/18= 136.7222222
ANSWER: Mean is =136.7222 or 136.72
ANSWER: Median is = 150
Answer: Mode is = 164
Midrange is = 168
Q1: 18
Q3: 62
1 solutions

Answer 261154 by Fombitz(13828) on 2010-11-05 07:51:09 (Show Source):

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Mean is correct.
.
.
Median is incorrect.
M=%28133%2B150%29%2F2=141.5

.
.
Mode is correct.
.
.
Midrange is incorrect.
MR=%2879%2B178%29%2F2=128.5

.
.
To calculated

, break the ordered data in half.
Take the first half.
79,93,97,98,111,124,124,126,133
Find the median of the first half.
Q1=111

.
.
.
To calculated

, break the ordered data in half.
Take the second half.
150,150,164,164,164,164,171,171,178
Find the median of the second half.
Q1=164

Evaluation_Word_Problems/366434: Sove the logarithmic equation.
ln(x+1)-ln(x-2)=ln5
1 solutions

Answer 261153 by Fombitz(13828) on 2010-11-05 07:37:10 (Show Source):

You can put this solution on YOUR website!
ln%28x%2B1%29-ln%28x-2%29=ln%285%29

ln%28%28x%2B1%29%2F%28x-2%29%29=ln%285%29

Distributive-associative-commutative-properties/366468: solve for d: 3/4(5-d)=10
1 solutions

Answer 261152 by Fombitz(13828) on 2010-11-05 07:34:16 (Show Source):

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%283%2F4%29%285-d%29=10

Now solve for

test/366223: http://img258.imageshack.us/img258/6640/factor.jpg
1 solutions

Answer 261096 by Fombitz(13828) on 2010-11-04 23:19:50 (Show Source):

You can put this solution on YOUR website!
13x-11%2B39ax-33a=13x-11%2B3a%2813x-11%29

expressions/366239: 30=5(r/5-3)
1 solutions

Answer 261094 by Fombitz(13828) on 2010-11-04 23:17:22 (Show Source):

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30=5%28r%2F5-3%29

Expressions-with-variables/366206: what is three x to the fourth power when x equals 5
1 solutions

Answer 261093 by Fombitz(13828) on 2010-11-04 23:16:04 (Show Source):

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3x%5E4=3%285%5E4%29=3%28625%29=highlight%281875%29

Polynomials-and-rational-expressions/366177: Solve. 6z3 – 27z2 + 12z = 0

1 solutions

Answer 261092 by Fombitz(13828) on 2010-11-04 23:14:52 (Show Source):

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6z3+%96+27z2+%2B+12z+=+0

Two solutions:
highlight%28z=0%29

.
.

z+=+%289+%2B-+sqrt%28+%28-9%29%5E2-4%2A2%2A6+%29%29%2F%282%2A2%29+

z+=+%289+%2B-+sqrt%28+81-48%29%29%2F%284%29+

highlight%28z+=+%289+%2B-+sqrt%28+33%29%29%2F%284%29%29+

Trigonometry-basics/366199: How Do I Sketch The function:
y=4 Sin (2x+(pi/6))-3
1 solutions

Answer 261091 by Fombitz(13828) on 2010-11-04 23:11:40 (Show Source):

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Expressions-with-variables/366405: factor 49y^2-25x^2
1 solutions

Answer 261090 by Fombitz(13828) on 2010-11-04 23:09:22 (Show Source):

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49y%5E2-25x%5E2=%287y-5x%29%287y%2B5x%29

Equations/366270: 3x+4/x-2 = 5
1 solutions

Answer 261089 by Fombitz(13828) on 2010-11-04 23:07:08 (Show Source):

You can put this solution on YOUR website!
%283x%2B4%29%2F%28x-2%29+=+5

Functions/366345: f(x)=2x^2-3x
1 solutions

Answer 261088 by Fombitz(13828) on 2010-11-04 23:04:47 (Show Source):

You can put this solution on YOUR website!
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C0%2C2x%5E2-3x%29

.
.
.
What's the question??

test/366403: Solve 3x+8y=26 solve for x
1 solutions

Answer 261087 by Fombitz(13828) on 2010-11-04 23:03:36 (Show Source):

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3x%2B8y=26

Geometry_Word_Problems/366398: The circle has an area of 100 square meters. If the radius of the circle is 5x+1 find the value of x in meters
1 solutions

Answer 261086 by Fombitz(13828) on 2010-11-04 23:02:51 (Show Source):

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pi%285x%2B1%29%5E2=100

highlight%28x=%28sqrt%28100%2Fpi%29-1%29%2F5%29

Exponents/366187: Simplify the expression if possible.
e^-6ln(t)
1 solutions

Answer 260944 by Fombitz(13828) on 2010-11-04 16:34:19 (Show Source):

You can put this solution on YOUR website!
e%5E%28-6%2Aln%28t%29%29=e%5E%28ln%28t%29%29%5E%28-6%29=t%5E%28-6%29=1%2Ft%5E6

Probability-and-statistics/366188: What is the probbility when drawing 3 queens in a row from a standard deck of cards when the drawn card is returned to the deck each time
1 solutions

Answer 260943 by Fombitz(13828) on 2010-11-04 16:32:34 (Show Source):

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P%28Q%29=4%2F52=1%2F13

.
.
.

P%283Q%29=P%28Q%29%2AP%28Q%29%2AP%28Q%29=%281%2F13%29%5E3=1%2F2197

Polynomials-and-rational-expressions/366191: what is the answer to s/6- 2/9=0
1 solutions

Answer 260940 by Fombitz(13828) on 2010-11-04 16:31:08 (Show Source):

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s%2F6-+2%2F9=0

Length-and-distance/366114: Evening Everybody
Stuck on this question. (trying to get back in to the swing of things so i can enrol on a course)
i) Given that F.r is the work done by a force F in moving a body through displacement r. Find the work done by the force F= 3i+7k. if it causes a body to move from the point A with coordinates (1,1,2) to the point B with coordinates (7,3,5)
ii) Obtain unit vectors in each of the directions of f=i+j+3k and s=2i-j+k. Hence show that 48/sqrt66 joules is the work done when a force of magnitude 6 newtons in the direction f moves its point of application a distance 2 metres parallel to s .
Really appreciate help on this.
1 solutions

Answer 260939 by Fombitz(13828) on 2010-11-04 16:29:23 (Show Source):

You can put this solution on YOUR website!
Find