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richwmiller answered: 9124 problems
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Surface-area/253225: The area of a trapezoid is found using A = 1/2 (b1 + b2)h where b1 is one base, b2 is the second base, and h is the height. Suppose a trapezoid has a base of 5x, another base of 9x, and a height of 8xy. What is the area?
1 solutions

Answer 185493 by richwmiller(9135) About Me  on 2010-01-03 13:02:34 (Show Source):
You can put this solution on YOUR website!
A = 1/2 (b1 + b2)h
Just plug in the values given
A=1/2(9x+5x)*8xy
A=1/2(14x)+8xy
A=7x+8xy
A=x(7+8y)


Graphs/253223: A company manufactures bicycles and skateboards. The company’s daily production of bicycles cannot exceed 10, and its daily production of skateboards must be less than or equal to 12. The combined number of bicycles and skateboards cannot be more than 16. If x is the number of bicycles and y is the number of skateboards, which graph correctly represents the region that contains the number of bicycles and skateboards the company can manufacture daily?

1 solutions

Answer 185490 by richwmiller(9135) About Me  on 2010-01-03 12:59:35 (Show Source):
You can put this solution on YOUR website!
Are you asking us to draw the graph or view the graph and answer questions based on your provided graph?


Probability-and-statistics/253224: a fair coin is tossed 3 times,
1. what's the probability of getting two heads?
2. what's the probability of getting three heads?
3. what's the probability of getting number of heads greater than number of tails?
1 solutions

Answer 185488 by richwmiller(9135) About Me  on 2010-01-03 12:57:34 (Show Source):
You can put this solution on YOUR website!
probability of one head is 50%=.5=1/2
1.-two heads 1/2*1/2
2.-three 1/2*1/2*1/2
3. - I don't know. I'll have to think about that one. There are some tutors here who are very good at probability


Radicals/253156: ^2(^3-2^2)
1 solutions

Answer 185485 by richwmiller(9135) About Me  on 2010-01-03 12:46:38 (Show Source):
You can put this solution on YOUR website!
You can't start out with ^.
2^2 is 2 squared.


Surface-area/253158: Identify 2 planes in the room, other than its wall, ceiling and floor which are
a. parallel
b. perpendicular
c.parallel to the floor
d. perpendicular to the floor
e. parallel to an edge
f. perpendicular to an edge on the floor
No given drawing
1 solutions

Answer 185484 by richwmiller(9135) About Me  on 2010-01-03 12:44:26 (Show Source):
You can put this solution on YOUR website!
Are you counting doors and windows as separate planes? Are you talking about furniture?
Pretty much everything is covered with ceiling floor and walls.


Matrices-and-determiminant/253174: 1)Find an LU factorization of the matrix A below.
A=
1 4 -1 5
3 7 -2 9
-2 -3 1 -4
-1 6 -1 7
1 solutions

Answer 185474 by richwmiller(9135) About Me  on 2010-01-03 12:12:13 (Show Source):
You can put this solution on YOUR website!
http://en.wikipedia.org/wiki/LU_decomposition
Hope this helps.


Equations/253164: please help me with me if you can send a literature for ekuacinet exponential spepse is strictly necessary from my need to pregaditi up to date 8.01.2010
1 solutions

Answer 185473 by richwmiller(9135) About Me  on 2010-01-03 12:07:50 (Show Source):
You can put this solution on YOUR website!
Is that English?
http://sq.wikipedia.org/wiki/Ekuacionet_e_Maksuellit


Parallelograms/253221: Please help me solve this problem:
MTSR is a parallelogram. MR= _______ MT=_______
MR is 2y-10; MT is 3x+6; TS is y-3; and RS is 2x+10
What would the y stand for, and what would the x stand for?
1 solutions

Answer 185471 by richwmiller(9135) About Me  on 2010-01-03 12:04:14 (Show Source):
You can put this solution on YOUR website!
We have a parallelogram which means that opposite sides are the same size and parallel.
So the opposite sides MR and TS are equal in size
2y-10=y-3
and MT and RS are equal
3x+6=2x+10
solve each and find x and y
y=7
x=4
I leave something for you to do.


Geometry_Word_Problems/253220: the width of a rectangle is 5 meters less than its length. the area is 84 square meters. find the dimensions of the rectangle.
1 solutions

Answer 185468 by richwmiller(9135) About Me  on 2010-01-03 11:59:05 (Show Source):
You can put this solution on YOUR website!
This problem could be in word problems geometry or quadratic equations.
Area=L*W
W=L-5
substitute L-5 for W
84=L*(L-5)
84=L^2-5L
L^2-5L-84=0
we ant factors of 84 with a difference of 5
1,84
2,42=6*7=3*2*7
3,14
4,21
6,14
7,12
7 and 12 will do
We want the larger number to be negative
(L-12)(L+7)=0
L=12 since a rectangle can't have a negative size of 7
W=L-5=7


Rational-functions/253187: I don't understand what they mean by graph of interval [-4,10]looks like and explain it I have been sitting up all night trying to understand some of these problems and I just can't comprehend what they are saying, I know how to read a graph once I figure out how to work out the equations.

baybay2763@email.phoenix.edu
carol2763@yahoo.com

1 solutions

Answer 185464 by richwmiller(9135) About Me  on 2010-01-03 11:48:43 (Show Source):
You can put this solution on YOUR website!
Your exact question was asked here.
http://wiki.answers.com/Q/Describe_what_the_graph_of_interval_-4_10_looks_like
Just plot the point. The answers says to plot the point.
If the link doesn't work just Google "graph of interval" and it should be the second result which is at answers.com


Numbers_Word_Problems/253168: AB
+BA
______
CD4
In the correctly worked addition problem above, each letter represents a different nonzero digit. What is one possible value of the two-digit number represented above as AB ?
(A) 74 (B) 31 (C) 86 (D) 47 (E) 95
option: (c)86

1 solutions

Answer 185462 by richwmiller(9135) About Me  on 2010-01-03 11:42:26 (Show Source):
You can put this solution on YOUR website!
We know the sum must end in 4
74+47 ends in 1
31+13 ends in 4 but has only two digits
86+68 ends in 4 and has three digits sum is 154
47+74 ends in 1 same as A)
95+59 ends in 4 and has three digits sum is 154
A,B, C and D are all unique so 95 and 59 can't use the 5 again in the sum
So the only acceptable answer is 86 and 68.


Polynomials-and-rational-expressions/253219: I was wondering if I got this problem right. Multiple polynomial. (5a-2b)^2 The answer I got was 25a^2-20ab+4b^2. Is this right?
1 solutions

Answer 185459 by richwmiller(9135) About Me  on 2010-01-03 11:32:14 (Show Source):
You can put this solution on YOUR website!

I get
25a^2-20ab+4b^2
which looks a lot like your answer.


Polynomials-and-rational-expressions/253209: I have a bad time with word problems. Please help me with this:
Junior's boat will go 15 mph in still water. If he can go 12 miles downstream in the same amount of time as it takes to go 9 miles upstream, then what is the speed of the current?
I know that we have to find the current so do I subtract from the original 15 mph? downstream = x-3 and upstream = x-6? Pleas help me.
1 solutions

Answer 185456 by richwmiller(9135) About Me  on 2010-01-03 11:27:40 (Show Source):
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downstream (with the current) you add x the speed of the current
upstream you subtract x the speed of the current
rt=d
we have the times equal but distance and speed different
since the times are the same let's solve for t
t=d/r
downstream
t=12/(15+x)
upstream
t=9/(15-x)
since t=t we will set them equal
12/(15+x)=9/(15-x)
multiply both sides by (15+x)
12=9*(15+x)/(15-x)
multiply both sides by (15-x)
12(15-x)=9*(15+x)
divide both sides by 3
4*(15-x)=3(15+x)
60-4x=45+3x
subtract 45 from both sides
15-4x=3x
add 4x to both sides
15=7x
15/7=x
2 1/7 mph=x speed of current


Polynomials-and-rational-expressions/253212: A water tank has an inlet pipe and a drain pipe. A full tank can be emptied in 30 minutes if the drain is opened and empty tank can be filled in 45 minutess with the inlet pipe opened. If both pipes are accidently opened when the tank is full, then how long would it take to empty the tank?
I believe this is a trick question and can possible be unknown.
1 solutions

Answer 185451 by richwmiller(9135) About Me  on 2010-01-03 11:15:01 (Show Source):
You can put this solution on YOUR website!
We had a similar problem in the last week or so.
This version starts with a full tank and drains faster than it fills.
t/30-t/45=1
Let's think about this.
If the fill pipe were closed it would take 30 minutes
So after 30 minutes the original water is gone.
In the meantime, it has filled up for 30 minutes. Let's deal with a complete refill.
It can fill in 45 minutes but has only has 30 minutes so it refilled 2/3
So after 45 minutes it will have filled again but the first fill is gone and the drain has had 15 minutes to empty it.
So it emptied half of it. To empty all of it it needs another 45 minutes.
So it would take 90 minutes to empty the full tank with the fill pipe opened.



Length-and-distance/253215: my name is tamesha i need a lot of help in geometry my teacher doesn't speak that much English and i just really need help
use the distance formula to decide whether pq=qr
p(4,-4)
q(1,-3)
r(-1,-3
can u please help me with this problem and show me a easy way to do them please thanks u so much!!!
1 solutions

Answer 185445 by richwmiller(9135) About Me  on 2010-01-03 10:57:15 (Show Source):
You can put this solution on YOUR website!
You need to find the distance between two points.
Check out this page for examples.

http://www.purplemath.com/modules/distform.htm
You need to find the distance between p and q
p(4,-4)
q(1,-3)
Then you need to find the distance between q and r
q(1,-3)
r(-1,-3)
Then you have to decide if they are the same distance


Human-and-algebraic-language/253216: 14 more than two times Johnny's age is the same as 6 less than three times his age. What is his age?
I apologize..it has been awhile sense I have had a real teacher to help me with things, I have not done word problems in a long time..
2xJ'sAge + 14...6-.....Bah..I haven't the common knowledge of this..I feel like this should be very easy but yeah, what I wrote is my guess, and a bad one at that..
1 solutions

Answer 185441 by richwmiller(9135) About Me  on 2010-01-03 10:49:47 (Show Source):
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2j+14=3j-6
14 more means add 14
two times means two times
6 less means subtract 6
three times means three times
is the same as means equals
The key to word problems is converting normal language to algebra.


Sequences-and-series/253211: four consecutive multiples of 5 add up to 4130. what is the largest number?
1 solutions

Answer 185439 by richwmiller(9135) About Me  on 2010-01-03 10:45:19 (Show Source):
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x+x+5+x+10+x+15=4130
4x+30=4130
4x=4100
x=1025
1030
1035
1040


Length-and-distance/253208: how do you find the coordinates of a triangle's vertices by just having the coordinates of its midpoints?
1 solutions

Answer 185438 by richwmiller(9135) About Me  on 2010-01-03 10:40:52 (Show Source):
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I would say you have your work cut out for yourself.
Any line connecting the midpoints is parallel to a side of the original triangle
Pick two of the points.
Find the line that goes through them.
Get the slope
Plug in an the x,y.
Use the same slope. Get the line.
Do it two more times.
Find where those lines intersect.
The intersections will be the vertices.



Sequences-and-series/253192: +1, 0, –1, +1, 0, –1, +1, 0, –1 . . . . and so on, where the last number is +1, has a sum of
(A) +1 (B) –1 (C) +2 (D) 0 (E) –2
1 solutions

Answer 185436 by richwmiller(9135) About Me  on 2010-01-03 09:58:14 (Show Source):
You can put this solution on YOUR website!
I moved your question to the proper heading.


Triangles/253205: How do you find the missing side of a right triangle when the hypotenuse is 14 and the base is 9?
1 solutions

Answer 185435 by richwmiller(9135) About Me  on 2010-01-03 09:56:41 (Show Source):
You can put this solution on YOUR website!
The Pythagorean theorem which is a^2+b^2=c^2
where c is the hypotenuse and a nd b are the legs
So we have 9^2+b^2=14^2
Multiply it out and solve for b the other leg(side).


Linear-equations/253204: which ordered pair is a solution of the equation 5x+3y=-2 a.(0,1) b. (1, -1) c. (-1, 1) d. (0,1)
1 solutions

Answer 185434 by richwmiller(9135) About Me  on 2010-01-03 09:54:18 (Show Source):
You can put this solution on YOUR website!
Just try each ordered pair and see if they are equal or not equal
a and d
If x =0 does y =1? No
b
if x=1 does y=-1 No
c
If x=-1 does y=1 yes so c is the answer
I suspect you copied something incorrectly since choices a and d are the same.


Polynomials-and-rational-expressions/253202: which of the following is a polynomial? Explain.
a)6x^2 + 3x
b)6x^2 + 3/x
c)6x^-2 + 3x
d)6x^-2 + 3/x
1 solutions

Answer 185431 by richwmiller(9135) About Me  on 2010-01-03 09:50:05 (Show Source):
You can put this solution on YOUR website!
C and D are not because they have negative exponents.
B has a term divided by x and so isn't
which leaves A which is .


Probability-and-statistics/253201: a certain club has 25 regular members.
(1) in how many ways can a president,vice precedent and a secretary be selected?
1 solutions

Answer 185430 by richwmiller(9135) About Me  on 2010-01-03 09:45:50 (Show Source):
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There are 25 ways to choose the president.
Then there are 24 ways to choose the vice president
Then there are 23 ways to choose the secretary.
25*24*23 ways to choose all three


Trigonometry-basics/253198: 20x6-7x5-6x4-500x4+175x3+150x2 Factoring this equation?
1 solutions

Answer 185429 by richwmiller(9135) About Me  on 2010-01-03 09:43:13 (Show Source):
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20x^6-7x^5-6x^4-500x^4+175x^3+150x^2
First take out x^2
x^2*(20x^4-7x^3-6x^2-500x^2+175x+150)
This conveniently arranged into two parts- notice the x^2 twice -6x^2-500x^2
20x^4-7x^3-6x^2=x^2(4x-3)(5x+2)
-500x^2+175x+150=-25(4x-3)(5x+2)
so now we have
x^2*(4x-3)(5x+2)(x^2-25)
and finally
x^2*(x-5)*(x+5)*(4x-3)*(5x+2)



Miscellaneous_Word_Problems/253178: What is the greatest common factor of 105 and 126?
(A) 3 (B) 7 (C) 9 (D) 21 (E) 35

1 solutions

Answer 185427 by richwmiller(9135) About Me  on 2010-01-03 09:25:04 (Show Source):
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105=5*3*7
126=3*6*7
the largest factor of each is 3*7=21


Geometric_formulas/253190: How do you find the area of a parallelogram with sides 8 and 14 and an included angle of 60 degrees?
1 solutions

Answer 185422 by richwmiller(9135) About Me  on 2010-01-03 09:17:41 (Show Source):
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Draw your parallelogram with sides 8 and 14 with angle of 60 degrees with the 60 angle at the base on the left.
If one angle is 60 the opposite angle is also 60.
The remaining angles are 120 each.
Now draw the height (altitude) from the 120 angle to the base .
We now have a right triangle with angles 30 60 90. We know that the sides in a 30 60 90 triangle are proportioned 1:sqrt(3):2
Now since the hypotenuse is 8 the triangles proportions are multiplied by 4.
so the altitude is 4sqrt(3)
We are not told where the 60 degree angle is.
I choose to make the base 14 and the altitude is 4sqrt
So the area is base times height which is 14*4sqrt(3)=64sqrt(3)
If the base is 8 then the height is 7sqrt(3) and the area is 8*7sqrt(3) or 56sqrt(3)


Miscellaneous_Word_Problems/253186: In Country X there are only 3 coins, the values of which are 1, 3, and 10 pillas. What is the set of pilla values you could give someone if you have 1 coin of each type and can only give an odd number of coins?
(A) {14 } (B) { 1,3 } (C) {1,3,10 } (D) {1,3,10,14 }
(E) {1,3,4,10,11,13,14 }
1 solutions

Answer 185415 by richwmiller(9135) About Me  on 2010-01-03 08:52:04 (Show Source):
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(E) {1,3,4,10,11,13,14 }
With 1,3,and 10, you can make all of the above values.


Miscellaneous_Word_Problems/253144: a housing project has 1822 units. there are twice as many two-bedrooms units as there are one-bedroom units, and 250 fewer three bedroom units than one-bedroom units, how many of each kind of units are there?
1 solutions

Answer 185402 by richwmiller(9135) About Me  on 2010-01-03 00:14:15 (Show Source):
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t+o+r=1822
2o=t
o=t/2
o-250=r
2o+o+o-250=1822
4o-250=1822
4o=1822+250
r=three bed
o=one bed
t=two bed
o=518
t=1036
r=268


Signed-numbers/253152: This is not acually for this topic, I need help on adding, subtracting, multiplying and dividing positive and negative numbers. How do I do this?
Example; -23- 73=???
1 solutions

Answer 185401 by richwmiller(9135) About Me  on 2010-01-03 00:05:39 (Show Source):
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-23-73=-96
Think of it as adding two regular numbers but they both have a minus sign.
I am sure you can do 73-23=50 and -23+73=50
also you can think of it as I owe John 73 cents and I owe Mary 23 cents
James owes me 15 cents
-73-23+15=-93+15=-78
What you owe is negative (going out)and what they owe you is positive. (coming in)


Word_Problems_With_Coins/253148: Nikka has 4 times as many 25-centavo coins as she has 1-peso coins. how many 1-peso coins does she have if the value of the coins is Php24.00?
1 solutions

Answer 185399 by richwmiller(9135) About Me  on 2010-01-02 23:58:13 (Show Source):
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c=4p
.25c+p=24
substitute 4p for c
1/4*4p+p=24
2p=24
p=12
48=c



Geometry_proofs/253140: Write a two column proof
Given PQ is congrunt to QR and PT is congrunt to RT
Prove QT bisects
1 solutions

Answer 185385 by richwmiller(9135) About Me  on 2010-01-02 21:53:09 (Show Source):
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"Congrunt" aka "con grunt" is what prisoners do on the chain gang.
Try congruent.
Given PQ is congruent to QR and PT is congruent to RT
Prove QT bisects How about giving us a clue as to what this object is?
Is it a triangle? circle? rhombus?
My guess is that it is an isosceles triangle with equal sides PT and RT.
So QT bisects PQR -definition of bisect.
QED