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 wyckedjester October 21st, 2012 12:32 PM

System of equations?

I hope this is the correct place to post this.

I have 4 equations with 4 unknowns. Let's assume the lower case letters represent different numbers that are known constants.

A = B/s
B = C/t
C = D/u

A + B + C + D = 10

Can anyone give me some hints on how to solve this? Thanks!

 Denis October 21st, 2012 12:57 PM

Re: System of equations?

Quote:
 Originally Posted by wyckedjester I have 4 equations with 4 unknowns. Let's assume the lower case letters represent different numbers that are known constants. A = B/s B = C/t C = D/u A + B + C + D = 10 Can anyone give me some hints on how to solve this? Thanks!
I may be missing something...but problem makes little sense:
just get any 4 numbers that equal 10: as example, 1,2,3,4: A=1, B=2, C=3, D=4.

A = B/s : s = B/A = 2/1 = 2
B = C/t : t = C/B = 3/2
C = D/u : u = D/C = 4/3

 mathman October 21st, 2012 01:44 PM

Re: System of equations?

Quote:
 Originally Posted by wyckedjester I hope this is the correct place to post this. I have 4 equations with 4 unknowns. Let's assume the lower case letters represent different numbers that are known constants. A = B/s B = C/t C = D/u A + B + C + D = 10 Can anyone give me some hints on how to solve this? Thanks!
C=D/u
B=C/t=D/(ut)
A=B/s=D/(stu)

D[1 + 1/u + 1/(ut) + 1/(stu)] = 10

I assume you can go from here.

 wyckedjester October 22nd, 2012 01:16 AM

Re: System of equations?

Quote:

Originally Posted by mathman
Quote:
 Originally Posted by wyckedjester I hope this is the correct place to post this. I have 4 equations with 4 unknowns. Let's assume the lower case letters represent different numbers that are known constants. A = B/s B = C/t C = D/u A + B + C + D = 10 Can anyone give me some hints on how to solve this? Thanks!
C=D/u
B=C/t=D/(ut)
A=B/s=D/(stu)

D[1 + 1/u + 1/(ut) + 1/(stu)] = 10

I assume you can go from here.

Thanks! That worked perfectly! Never would have thought to do it that way...

 skipjack October 22nd, 2012 05:31 AM

Any way that you've been taught (or can find) to solve simultaneous linear equations would have worked.

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