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#1 2015-02-21 17:43:07
- stevesy
- Member
- Registered: 2015-02-21
- Posts: 9
Algebra - Rearranging an equation to isolate a variable
Hi, I need some help understanding the following problem, the goal of which is to solve the equation in terms of Rt. A friend of mine did the first 4 lines and I finished the rest. Firstly, can you tell me whether the answer I arrived at is correct, and secondly can you explain to me how my friend got from the 2nd to the 4th line?
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#2 2015-02-21 18:05:21
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Algebra - Rearranging an equation to isolate a variable
Hi;
Please check line 4 to 5. It looks like you divided the top and bottom by R1 + R2 which is not correct.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#3 2015-02-22 00:12:49
- CIV
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- Registered: 2014-11-09
- Posts: 74
Re: Algebra - Rearranging an equation to isolate a variable
Here's my attempt:
Answer:
Skipped a few steps.
Which leavs us with this:
I don't know if this is right. If someone can confirm that would be great. I am only a student so I can't say for sure it's right. Spent a good portion of the night trying to figure this out when I should of been doing my homework.
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#4 2015-02-22 01:19:59
- stevesy
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- Registered: 2015-02-21
- Posts: 9
Re: Algebra - Rearranging an equation to isolate a variable
Hi;
Please check line 4 to 5. It looks like you divided the top and bottom by R1 + R2 which is not correct.
Yes, that's what I did bobbym. Would I be right in saying that I could have done that had the denominator been [ADC(R1 + R2) * 10230R2]?
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#5 2015-02-22 01:24:49
- stevesy
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- Registered: 2015-02-21
- Posts: 9
Re: Algebra - Rearranging an equation to isolate a variable
Spent a good portion of the night trying to figure this out when I should of been doing my homework.
lol thanks for having a go at it CIV, sorry for interfering with you're homework ; ]
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#6 2015-02-22 06:13:51
- CIV
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- Registered: 2014-11-09
- Posts: 74
Re: Algebra - Rearranging an equation to isolate a variable
No problem.
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#7 2015-02-22 06:47:37
- stevesy
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- Registered: 2015-02-21
- Posts: 9
Re: Algebra - Rearranging an equation to isolate a variable
I think this might be the answer:
Last edited by stevesy (2015-02-23 03:02:45)
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#8 2015-02-22 09:43:20
- CIV
- Member
- Registered: 2014-11-09
- Posts: 74
Re: Algebra - Rearranging an equation to isolate a variable
I think the (R1 + R2) in the numerator and demonitor like that would all cancel out leaving 1's. I don't even think my attempt is right. I don't have time to keep trying even though I would really love to.
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#9 2015-02-22 13:31:17
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Algebra - Rearranging an equation to isolate a variable
Would I be right in saying that I could have done that had the denominator been [ADC(R1 + R2) * 10230R2]?
Yes, then it would have been legal.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#10 2015-02-23 03:03:58
- stevesy
- Member
- Registered: 2015-02-21
- Posts: 9
Re: Algebra - Rearranging an equation to isolate a variable
Thanks bobbym : ] I simplified the answer a little more.
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#11 2015-02-23 06:07:15
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Algebra - Rearranging an equation to isolate a variable
What did you get now for a final answer?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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