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3x+y=0
x=0
1 solutions
Answer 256555 by Fombitz(13828) on 2010-10-21 08:17:39 (Show Source):
You can put this solution on YOUR website!Parallel lines have slopes that are identical.

Perpendicular line have slopes that are negative reciprocals.

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.
.

Parallel, 
Perpendicular, 
.
.
.

Slope is undefined.
Parallel, slope is undefined.
Perpendicular,  .
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Probability-and-statistics/359556: Determine whether each of the distributions given below represents a probability distribution. Justify your answer.
x
1
2
3
4
P(x)
1/12
5/12
1/3
1/12
(A)
x
3
6
8
P(x)
2/10
.5
1/5
(B)
x
20
35
40
50
P(x)
0.4
-0.2
0.5
0.3
(C)
1 solutions
Answer 256554 by Fombitz(13828) on 2010-10-21 08:14:55 (Show Source):
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real-numbers/359557: Can you help me with this problem?
find slope if it exists of the line containing the pair of points (-2,-16,
(-9, -18)
Slope is ???
If I do y2 - y1/x2 - x1
-16 - (-18) / -2 - (-9) = -16 + 18/ -2 +9
= (2, 7)
Would the slope of the line be 2? Or (2,7)?
Thanks for your help
1 solutions
Answer 256553 by Fombitz(13828) on 2010-10-21 08:11:45 (Show Source):
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Length-and-distance/359558: From the distance from (-4,-1) to the line defined by y=-2x+1. Express as a radical or a number rounded to the nearest hundredth. 1 solutions
Answer 256552 by Fombitz(13828) on 2010-10-21 08:08:42 (Show Source):
You can put this solution on YOUR website!1. 
The closest distance is formed by the line perpendicular to  that goes through the point (-4,-1).
To find the perpendicular line, use the slope since perpendicular lines have slopes that are negative reciprocals.

Now use the point slope form of a line,

2. 
Now that you have both lines, find the intersection of the two lines.
The distance you're after is the distance from point (-4,-1) to the intersection point.
Substitute eq. 1 into eq. 2 and solve for  .

Then from eq. 1,

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.

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.
.
Now use the distance formula to find the distance from (-4,-1) to (0,1).
 or approximately,
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Mixture_Word_Problems/359560: Hi, doing my statistic homework and I need help. The question is you spin a number wheel that has 19 numbers 950 times. The random variable represents the the winning numbers on each spin of the wheel. I don't really get the question and how I'm suppose to do it.
1 solutions
Answer 256551 by Fombitz(13828) on 2010-10-21 07:57:19 (Show Source):
You can put this solution on YOUR website!Each number has an equal probability of being chosen.
So when you spin 950 times, on average, you would get each number 50 times.
Since 
So the random variable would look like,
(  ,  )
(  ,  )
(  ,  )
(  ,  )
.
.
.
(  ,  )
(  ,  )
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Polynomials-and-rational-expressions/359440: When asked to solve the equation (x + 3)(2x - 1) = 5 a student proceeded as follows:
x+3=5 or 2x-1=5
x=2 or x=3
Describe, in your own words, what this student did wrong and what he/she should have
done.
1 solutions
Answer 256549 by Fombitz(13828) on 2010-10-21 06:25:59 (Show Source):
You can put this solution on YOUR website!That would only work if their product equals 5 simultaneously.
So when one factor equals 5, the other equals 1.
When  ,  , but  , so then the product equals  as expected.
When  ,  , but  , so then the product equals  and not  as expected.
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Systems-of-equations/359427: Discuss whether the statement, (x + y)3 is equivalent to x^3 + y^3, is true or not.
Identify a pair of values of x and y for which this statement is true and another pair of values for which it is not true.
1 solutions
Answer 256545 by Fombitz(13828) on 2010-10-21 06:18:40 (Show Source):
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logarithm/359524: Solve for x. Please round answer to four decimal places.
2^(4/log base 3 (x)) = 1/256
I have tried to solve for x by
2^4/logbase3 x = 2^-8
and then I am stuck.
Please help 1 solutions
Answer 256543 by Fombitz(13828) on 2010-10-21 06:12:59 (Show Source):
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Square-cubic-other-roots/359541: Hi. I have x as a function of z(below). I need z as a function of x!
x=sqrt(z-1)(4z-1)/sqrt(3z-1)
I can't seem to figure it out in hand! So i tried to solve it on a ti89, but it only gives me strange answers involving irregular numbers. I also tried to solve it on mathcad, wiyhout any luck.
If i insert say 0,3 as z, i get 0,529. Shouldn't i then be able to find a equation for z, where i can insert the 0,529 and get 0,3?
Is this possible or what? 1 solutions
Answer 256539 by Fombitz(13828) on 2010-10-21 06:05:53 (Show Source):
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Linear-equations/359216: write an equation of the line containing the given points
1. A(2,7), B(3,4) 2. P(-1,3), Q(0,4) 3. S(10,2), T(2,-2) 4. D(7,-4), E(-5,2)
1 solutions
Answer 256379 by Fombitz(13828) on 2010-10-20 16:14:32 (Show Source):
You can put this solution on YOUR website!Find the slope first.

.
.

Then use the point-slope form of a line with either point,

.
.
.

.
.
.
Follow the same procedures for the remaining problems.
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absolute-value/359211: Hello! I'm a ninth grader who needs help with graphing functions with absolute value. For instance, the first problem in my Algebra II/Trigonometry homework is:
f(x) = |x|
I already understand what a function is, as well as the absolute value, it's just my teacher didn't explain very thoroughly on how to graph them. I'd be very grateful if you were able to give me a step-by-step explanation on how to graph this problem. Thank you so much in advance for voluntarily helping students like me.
Sincerely,
sunshine2739 1 solutions
Answer 256376 by Fombitz(13828) on 2010-10-20 16:09:49 (Show Source):
You can put this solution on YOUR website! when 
.
.
.

.
.
.
 when 
.
.
.

.
.
.
Now put those two together,

.
.
.

.
.
.
The key is the argument (inside the absolute value brackets).
Make sure you understand how to find up the limits.
So if the function is,
 when
 when
 when 
.
.
 when
 when 
.
.
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Probability-and-statistics/359201: A sample of 4 different calculators is randomly selected from a group containing 17 that are defective and 36 that have no defects. what is the probability that atleast one of the calculators is defective? 1 solutions
Answer 256370 by Fombitz(13828) on 2010-10-20 15:53:42 (Show Source):
You can put this solution on YOUR website!P(good)= 
P(bad)= 
.
.
.
P(at least one bad)+P(none bad)=1
P(at least one bad)=1-P(non bad)
.
.
P(none bad)= 
P(at least one bad)= 
P(at least one bad)=
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Graphs/358811: use the slope-intercept form to graph the equation y=3/5x-3 1 solutions
Answer 256361 by Fombitz(13828) on 2010-10-20 15:38:17 (Show Source):
You can put this solution on YOUR website!Start with the y-intercept (  ,  ).
Slope is  and represents change in  over change in  .
 units change in  will give a  units change in  .
.
.
X: 
Y: 
.
.
(  ,  ) is another point on the line.
Plot the two points and connect them with a line.
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.
.
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