Question

Hi there,

I have a 3 part question that I have only been able to get one of the parts correct. Here is the attachment showing it. Please help me;

SOLVE FOR (a) and solve for (W).

I've managed to isolate (V) and solved it correctly. But only 1 out of 3 :/

Answer 1

sorry if its a weird size. you may have to zoom out or in heaps but it is there ....

Answer 2

If someone knows how to help me just with finding out (W) I would be extremely grateful..

Answer 3

what are your attempts? this is pretty basic restructing

Answer 4

hi, I have done about 30 other problems very similar and been able to do it, but there's something going wrong with this particular question Im not sure why.

I will start typing in what i'm doing with it.. Thanks!

Answer 5

k, ill check back once youve posted some stuff to look over the work and correct it as needed

Answer 6

I think whats throwing me is; why is the formula stated like this

(aW+B) x V ? why isn't it the usual V(aW+b). Does this change things?

Here are my workings;

W
n = -----------
(aW + b) x V

W = n (aW + b ) x V
W = (naw + nb) x V
W = nawV + nbV

W nbV
---- = w + ------
naV naV

W nbV
---- - W = -------
naV naV

1 nbV
W * (---- - 1) = ------
naV naV

W = ???? please help something's gone wrong.

Answer 7

x just means multiply ... nothing more in this case. you have to be able to distinguish that. unless your working with vectors and i dont think you are

Answer 8

my approach is similar, but without the n distribution

Answer 9

Hi there, no you're right Im not working in vectors. Argh the penny finally dropped!

Answer 10

W
n = ----------
V(aW+b)


W
aW + b = -------
nV


W
b = ------- - aW
nV


factor out the W

b = W(1/(nV) - a)


b
--------- = W
1/(nV) - a

simplify if needed

Answer 11

I've done a bunch more practice of these and after writing it up and retrying it I have now achieved the correct answer!

Answer 12

bnV
------ = W
1-anV

might be the simplest version of it that i can see

Answer 13

Trying to follow... sorry.. im sorry but what does this mean please?

b = W(1/(nV) - a)

and

1/(nV) - a

is that divided by? Im new to the site and ways of expressing things ...

Answer 14

Yes you're right,
the answer in the book is ;

bnV
------ = W
1-anV

Answer 15

without delving into the latex coding, i tried to make it look fraction like in text is all

Answer 16

\[\frac{this}{that}+other\]
this tends to slow down my computer

Answer 17

b = W/(nV) - aW

does it make sense up to here?

Answer 18

b = W
------
(nV) -aW

I think Im stuffing up and probably annoying you... cringe. Im sure I'll figure it out. Thanks for your help!

Answer 19

W
b= ----- - aW
(nV)

Answer 20

when reading proper mathical brackets ....

W/(nV) is read the W is divided by (n times V) this is one term

-aW is the second term, its subtracted from the first

b = W/(nV) - aW

Answer 21

yes

Answer 22

since we want W, and its common to both terms, factor it out

remember

ka + kb = k(a+b) , k is a common factor and 'undustributes'

Answer 23

Yes I see, thanks. You must end up with one left though right. If you cancel it out all together, its gone. Just to triple check I haven't missed the obvious..

Answer 24

Cool thank you so much for your patience :) Im a bit embarrassed at my level. Thanks again

Answer 25

forget levels ... focus on math

nothing 'cancel' it factors out, and a 1 is left in its place if thats how youwant to view it

b = W/(nV) - aW

b = W [1/(nV) - a*1]

then the rest is division and clearing fractions i spose

Answer 26

i saw you distributing the n up above, factoring is just the undoing of distribution.

k(a+b) distributes to: ka + kb

when terms have a common factor, we can 'undistribute' it ... factor it out

ka + kb = k (a+b)

Answer 27

Thank you. Why don't you cancel out these?:

Answer 28

sorry, FACTOR out? :)

Answer 29

the bottom Vo parts? you actually do

Answer 30

\[\frac{a}{k}+\frac{b}{k}\]
\[\frac1k(a+b)=\frac{(a+b)}{k}\]
its just another way of expressing it

Answer 31

See thats what I thought but the only way I could seem to get the correct answer was umm leaving them in - which sounds so not good when you say it out loud..

Answer 32

I am familiar with this;

(a+b)
------
k

Answer 33

but the

1
--- (a + b)
k


I will have to give some thought

Answer 34

hmm, it all really depends in what is considered a simplified enough form

\[\frac{273V}{V_o}=\frac{273V_o}{V_o}+t\]
\[\frac{273V}{V_o}=\frac{273\cancel{V_o}}{\cancel{V_o}}+t\]
\[\frac{273V}{V_o}=273+t\]
\[\frac{273V}{V_o}-273=t\]
\[273\left(\frac{V}{V_o}-1\right)=t\]

Answer 35

this is what i would consider a 'simplified' answer so i find these "correct" answer type things to be misleading

Answer 36

Yes. There is a possibility that possibly some of my answers are correct but expressed in a different form, but maybe not. Its all good practice for me to try and get the answer how they have it. Thank you for your time. I am going over your replies and writing them out etc. Thanks again :)

Answer 37

your welcome, its about 4am whre i am so im going to head to ... some place else i think, good luck

Answer 38

I gotta come clean, i do not understand how you "factored out this bit ...:

factor out the W

b = W(1/(nV) - a)

Answer 39

W/(nV) - aW

do both terms have a W?

Answer 40

WHAT !!??! 4am??? What are you doing? Where are you??

Answer 41

im typing out math stuff, in florida lol

Answer 42

se if this connects

2/3 + 2(5) what does this equal?

Answer 43

ha, cool :D Im in Melbourne Australia. Its not 4am is more like 6pm .. much more civilised !!

Answer 44

not sure if i could stand living upside down :)

Answer 45

it takes all my wits just to live standing sideways ;)

Answer 46

2/3rds + 10 right? so
10 2/3 ten and two thirds... right?

Answer 47

yes or improperly as 32/3

now lets factor out the 2, then add, then multiply it back in

2(1/3 + 5)

what do we get?

Answer 48

sorry what? I am not completely stupid I just dont quite get what you're asking

Answer 49

you're asking me to factor out the 2 in this:
2(1/3 + 5)

Answer 50

this is a specific example:

W/(nV) - aW is a generality, you said you werent completely sure why we can remove the W

Answer 51

then add.. what?

Answer 52

ok let me clarify please..

in this working of yours;

W
n = ----------
V(aW+b)


W
aW + b = -------
nV


W
b = ------- - aW
nV


factor out the W

b = W(1/(nV) - a)


b
--------- = W
1/(nV) - a

simplify if needed

Answer 53

making a point, we can factor out common factors, and the results are the same

2/3 + 5(2) is equivalent to 2(1/3 + 5)

proof

2/3 + 5(2) = 2/3 + 10 = 32/3

2(1/3 + 5) = 2(16/3) = 32/3

Answer 54

what needs clarification please

Answer 55

keep in mind that this is just one approach, and there is not any set in stone correct way to approach it.

Answer 56

sorry. I understand up till here. is this what you are saying:

Factor out the W

b = W(1/(nV) - a) as in, this means..,.


1
W * times ( -------- - a)
(nV)

Answer 57

lets review your appraoch while things load ...

Here are my workings;

W
n = -----------
(aW + b) x V

W = n (aW + b ) x V <-- no need to bring the V along but its here
W = (naw + nb) x V <-- distribution is fine
W = nawV + nbV <-- distribution, fine still

W nbV
---- = w + ------ this is where it goes haywire
naV naV


W = naWV + nbV , subtract the naWV

W - naWV= nbV ; factor out the W

W [1 - naV]= nbV ; divide to get W all alone


nbV
W = -----------
1 - naV

Answer 58

strategy; keep focus on what the objective is and gather all the like terms:

like terms have the common factor that can be factored out ....

Answer 59

comprehendo . Thanks for spelling it out you've been very patient! I get it :) Thanks heaps for your time. Things will be opening again for the next day by the time you leave home .. maybe you should consider sleep ha

Thanks again :)

Answer 60

sleep is for the weak lol :) think ill get some sleep good luck ;)

Answer 61

:)