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#1 2013-02-01 22:28:28

lokitwister
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3x-2y=1 how to find the value of x and y?

HI,
I am very weak in match, i have equation like
1. 3x-2y=1 h
2. 3x+y = x+3

Please help
Lokesh

 

#2 2013-02-01 22:29:44

bobbym
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Re: 3x-2y=1 how to find the value of x and y?

Hi;

What is that h doing there?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#3 2013-02-01 22:31:29

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

i m doing set theory

 

#4 2013-02-01 22:33:06

bobbym
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Re: 3x-2y=1 how to find the value of x and y?

I do not understand, aren't you solving a simultaneous set of linear equations? What has that to do with set theory? Is that h a variable?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#5 2013-02-01 22:33:28

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

quiz is this  .    find x and y if (3x+y, x-1) = (x+3, 2y-2x)

sorry h is mistake  , h is nothing

 

#6 2013-02-01 22:36:45

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

this question is from ordered pairs, so that first i have to find x and y

 

#7 2013-02-01 22:38:44

bobbym
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Re: 3x-2y=1 how to find the value of x and y?

I am getting x = 1 and y = 1.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#8 2013-02-01 22:41:45

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

yes, perfect,  is there any method or something else to find value of x and y?

 

#9 2013-02-01 22:45:23

bobbym
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Re: 3x-2y=1 how to find the value of x and y?

There are several methods:

Form the simultaneous set:





Do you know how to solve that?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#10 2013-02-01 22:47:35

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

no, i don't know

 

#11 2013-02-01 22:58:23

bobbym
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Re: 3x-2y=1 how to find the value of x and y?



Clean this one up a bit by subtracting x from both sides.



Clean up the second one



Add 2x to both sides



Subtract 2y from both sides.



Add one to both sides



We now have





Did you follow up to here?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#12 2013-02-01 23:05:58

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

how do you think what to add or not?

 

#13 2013-02-01 23:10:34

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

ya i got it till here, but what next to find x and y?

 

#14 2013-02-01 23:17:53

bobbym
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Re: 3x-2y=1 how to find the value of x and y?

how do you think what to add or not?

Just trying to get it into the form of all the variables on the left and all the numbers on the right so we can make the next bunch of moves.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#15 2013-02-01 23:26:23

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

ok, but what will be  the next step to find x value?

 

#16 2013-02-01 23:32:45

bobbym
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Re: 3x-2y=1 how to find the value of x and y?





We would like to subtract or add the bottom equation from the top one and make one variable disappear. But when I do that 2x - 3x = x, that did not disappear and y + (-2y) = y so no luck there either.

If I multiply the top equation by 3 I get





Now if I multiply the second equation by 2 I get





So I have changed the equations again to




In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#17 2013-02-01 23:43:45

lokitwister
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Re: 3x-2y=1 how to find the value of x and y?

Thanks, here i will find y

 

#18 2013-02-01 23:45:43

bobbym
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Re: 3x-2y=1 how to find the value of x and y?

Can you finish now or do you want me to do more?


Where did he go?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

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