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13410..13439 , 13440..13469 , 13470..13499 , 13500..13529 , 13530..13559 , 13560..13589 , 13590..13619 , 13620..13649 , 13650..13679 , 13680..13709 , 13710..13739 , 13740..13769 , 13770..13799 , 13800..13829, >>NextGraphs/359807: Let a and b represent the length of the sides of a right triangle and h the length of the hypotenuse. Find the missing side. a=2, b=10 1 solutions
Answer 256863 by Fombitz(13828) on 2010-10-21 22:34:39 (Show Source):
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Functions/359898: Determine the equation of the parabola with vertex,
a) (1,6) and passes through (0,-7)
b) (4,-5) and passes through (-1,-3)
thank you 1 solutions
Answer 256857 by Fombitz(13828) on 2010-10-21 22:27:56 (Show Source):
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Graphs/359744: I am trying to make a graph and the equation is: y= -x-2.
How do I solve this? I know the formula is: y=mx+b. Would the x be zero? 1 solutions
Answer 256740 by Fombitz(13828) on 2010-10-21 16:34:44 (Show Source):
You can put this solution on YOUR website!No, x and y are the variables.
When  ,  .
(0,-2)
Plot that point.

Now you can do it one of two ways.
Generate another point using the function or use the slope.
To generate another point, pick another x.
When  , 
(2,-4)
Plot that point, connect the points with a line.

.
.
.
The other way is to use the slope,  .
In this case, 
THe slope is the change in y divided by the change in x.
So if I move 1 unit in the x, then I move -1 units in the y.
To get another point, start with the y-intercept, (0,-2).
X: 
Y: 
(-1,-3) is another point on the line.
Plot it and connect the points with a line.

.
.
.
It's the same line. If I had moved 2 units in the x then I would have moved -2 units in the y (since  , then I would have been at point (3,-2).
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Linear-equations/359743: my first qustion is how do you graph the linear equation 3x+y=7
my second question is how do you write an equation for "parallel to x+2=0 with x-intercept (-1,0)" in a slope intercept form? 1 solutions
Answer 256737 by Fombitz(13828) on 2010-10-21 16:27:51 (Show Source):
You can put this solution on YOUR website!Find the intercepts.
Plot them, then connect them with the line.
To find the x-intercept, set  and solve for  .

(  ,  )
.
.
.
To find the y-intercept, set  and solve for  .

(  ,  )
.
.
.

.
.
.
Typically parallel lines have identical slopes.
However in this case, the slope for  or  is undefined.
It is a vertical line and cannot be represented with the slope intercept form,  .
It has the form  and since it passes through the point (-1,0), it has the exact form of  .

.
.
.
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Radicals/359732: Hello, could you please help me solve this equation. I initially tried solving by squaring both sides but the result seemed to be something awful. When I subtracted 4 from both sides and then squared both sides, my answer was x = 15/4
This is the equation:
4 + sqrt(10-x) = 6 + sqrt(4-x) solve for x
thank you. 1 solutions
Answer 256730 by Fombitz(13828) on 2010-10-21 16:00:34 (Show Source):
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Rectangles/359713: the diagonal of a rectangle is 15cm, and the perimeter is 38cm. What is the area? Is it possible to find the answer without finding the dimensions of the rectangle? 1 solutions
Answer 256725 by Fombitz(13828) on 2010-10-21 15:54:17 (Show Source):
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Miscellaneous_Word_Problems/359726: A chemistry experiment calls for a 20% solution of copper sulfate. You have 150 milliliters of a 30% solution. How many milliliters of an 18% solution should you add to get a 20% solution? 1 solutions
Answer 256723 by Fombitz(13828) on 2010-10-21 15:49:07 (Show Source):
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Probability-and-statistics/359724: 4. A company recruits personnel for its sales department on the basis of special tests designed to judge the potential of the candidates. The following table gives test scores and the mean daily sales for 9 executives.
a. Fit a regression line of Y on X.
b. Prepare a table of predicted values and residuals.
Mean daily Score(Y)
34 39 30 33 36 38 45 41 48
Test Score (X)
59 69 50 56 64 66 77 73 83
1 solutions
Answer 256717 by Fombitz(13828) on 2010-10-21 15:42:26 (Show Source):
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Probability-and-statistics/359390: I was just wondering if someone could double check my work on this problem:
A box contains 8 good parts and 4 defective parts. If a sample of 2 parts is drawn from the box at random (without replacement), what is the probability of each of the following:
Two good parts are selected. (my answer 8/12 * 7/11 = 14/33 or 42%)
Two defective parts are selected. (my answer 4/12 * 3/11= 1/11 or 9%)
One good part is selected first, and then one defective part is selected second?
(my answer 8/12 or 66% chance of good part first, 4/11 or 36% chance of defective part being chosen second 8/12 * 4/11 = 8/33 or 24% totalling a 24% chance)
Exactly one defective part out of the two is selected. (my answer ?)
Any input would be apprieciated!
1 solutions
Answer 256710 by Fombitz(13828) on 2010-10-21 15:34:49 (Show Source):
You can put this solution on YOUR website!1.Two good parts are selected.
 , Correct!
.
.
2.Two defective parts are selected.
 , Correct!
.
.
3.1st good, 2nd defective.
 , Correct!
.
.
Exactly one defective part out of the two is selected.
.
.
You already have half of the answer (  ).
What about if you choose a defective part first, then a good part.
That would give you 
P(exactly 1)= 
P(exactly 1)= 
.
.
Also,remember there are only 4 choices you can make, picking two parts.
GG- 
DD- 
GD- 
DG-  =??
Remember also that the sum of the probability for all of the events must be 1.
So you can solve this problem in two ways, or use the other way to check your work.
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Linear_Algebra/359720: This is a very simple question and it's embarassing to ask. I am being thrown off by the omition of a variable.
Given the piecewise defined function y={-2 if x=0, find f(0) Is this a trick question since there is not a variable accompanying the -2? It seems like it should state y={-2x if x=0, find f(0)
1 solutions
Answer 256705 by Fombitz(13828) on 2010-10-21 15:22:19 (Show Source):
You can put this solution on YOUR website!Yes, I think you're justing being thrown off.
If  , then  .
.
.
.
But if it stated  , then  , however if it was  when  , then  and I understand what you mean.
Typically piecewise functions don't give just one value, but there's no rule against it either.
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Matrices-and-determiminant/359714: I am attempting to help my daughter with her Algebra 2 homework. I got the problem set up but have no clue how to proceed from here. The problem is
(1 1 1
1 1 1
1 1 1)
The next part of the matrix which is to be multiplied is (4 over 9).
This the matrix, I think, that I need to work with.
The original problem states: 1 putt is a hole in one; 2 putts is a birdie; 3 putts is a par and 4 putts is a bogey.
Grace placed 18 holes of miniature golf. On each hole, sh made a birdie, a par, or a bogey. She made 4 more pars than birdies and bogeys combined. Her total score was 55. How many birdies did Grace get?
Now I am lost once I got the above problem set up. Can you please help? 1 solutions
Answer 256702 by Fombitz(13828) on 2010-10-21 15:11:21 (Show Source):
You can put this solution on YOUR website!First, name your variables.
No holes-in-one. So there are only three variables.
Let  be the number of birdies,  the number of pars,  the number of bogeys.
and each have a score of 2,3, and 4 respectively.
You know that
She played 18 holes.
1. 
"she has made 4 more pars than birdies and bogeys combined"

2. 
"Her total score was 55"
3. 
.
.
.
1. 
2. 
3. 
.
.
.
[A]= 
[x]= 
[b]= 
.
.
.
[A][x]=[b]
[x]=[A]inv[b]
.
.
.
det[A]= 
.
.
.
[A]= 
.
.
.
[x]= 
.
.
.
Grace got 3 birdies, 11 pars, and 4 bogeys.
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Mixture_Word_Problems/359596: Hello, I have two problems I need help with. Thanks
let p, q, and r be the following statement:
p: jamie is on the train.
q: sylvia is at the park.
r: nigel is in the car.
translate the following statement into english: (~q^p)arrow going to right ~r
construct a truth table for ~q V ~p 1 solutions
Answer 256696 by Fombitz(13828) on 2010-10-21 14:50:12 (Show Source):
You can put this solution on YOUR website!p: jamie is on the train.
q: sylvia is at the park.
r: nigel is in the car.
.
.
~p: jamie is not on the train
~q: sylvia is not at the park
~r: nigel is not in the car.
.
.
.
(~q^p)->~r
If (not q and p) then (not r)
Now just substitute,
If (sylvia is not at the park and jamie is on the train) then (nigel is not in the car)
.
.
.
p q ~p ~q (~q v ~p)
-----------------------------------
T T F F F
T F F T T
F T T F T
F F T T T
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