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**sherpa tensing****Member**- Registered: 2014-04-07
- Posts: 6

Hi Bobbym

The question asks for the answer to be left in surd form

I wondered if you could point me in the right direction on this quadratic equation = 3x²-4x-2=0

I used the formula -b +or -√b²-4ac divided by 2a. I got it down to x=4 _+ 2√10 divided by 6. Now, I cancelled the 2 by 6 getting it to become x= 4=_+ √10 divided 3, thinking this was the lowest form, I checked the answer but I was wrong.

It was given as x= 2_+√10 divided by 3. if you can understand my reasoning and my maths, I can not for the life in me see where (b) became 2 and didn't stay as 4...........help please if you can.

Regards ST

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

There are two roots:

For your answer of

you can just take a factor of 2 from the numerator and denominator.

**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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**sherpa tensing****Member**- Registered: 2014-04-07
- Posts: 6

Thanks Bobbym for your time.

I think I may be having a dyslexic mathematical moment. I knew there there would be 2 roots as X is squared, and can see how that comes about. I'm still slightly puzzled about "taking a factor of 2" do I just divide top and bottom by 2.......I think I'm going for a lie down in a darkened room

Regards ST

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

You could divide the numerator and denominator by 2.

**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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