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#1 2006-11-20 11:26:17

unique
Member
Registered: 2006-10-04
Posts: 419

can u help me solve this

solve

3
sqrt(2x + 3)  = 3


Desi
Raat Key Rani !

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#2 2006-11-20 11:57:29

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: can u help me solve this

The only difficult thing about this equation is the square root sign. You can get rid of that by squaring both sides, and then you'll have a nice, simple, linear equation to deal with.


Why did the vector cross the road?
It wanted to be normal.

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#3 2006-11-20 15:06:23

basmah
Member
Registered: 2006-10-02
Posts: 18

Re: can u help me solve this

yup....in steps it looks like:

√(2x+3) = 3
=> (√(2x+3))² = 3²
=> 2x+3 = 9
=> 2x = 9-3
=> 2x = 6
=> x= (6/2)
=> x=3

that would be if you have to all your steps.....well im sure you understand it now

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#4 2006-11-20 19:33:42

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: can u help me solve this

Yep. If you can, get rid of the square root sign (√). It makes life a whole lot easier.

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#5 2006-11-20 23:37:45

WiZaRd
Real Member
Registered: 2006-09-22
Posts: 570

Re: can u help me solve this

what was difficult in this question?


Be Happy!

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#6 2006-11-21 03:15:20

unique
Member
Registered: 2006-10-04
Posts: 419

Re: can u help me solve this

basmah wrote:

yup....in steps it looks like:

?(2x+3) = 3
=> (?(2x+3))² = 3²
=> 2x+3 = 9
=> 2x = 9-3
=> 2x = 6
=> x= (6/2)
=> x=3

that would be if you have to all your steps.....well im sure you understand it now

you know when you put

?(2x+3) = 3
there has to be a 3 on the top of the sqrt sign
like this is ? so teh three is on the top side of teh ? liek this
3?


i know how to do it that way that you just said but the 3 messed me up.


Desi
Raat Key Rani !

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#7 2006-11-21 03:29:09

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: can u help me solve this

Oh, so that's the third root? I see now. Well, in that case, you use exactly the same method except that you need to cube both sides to start with.

And then it's exactly the same question but with 27 on the right hand side instead of 9.


Why did the vector cross the road?
It wanted to be normal.

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#8 2006-11-21 03:39:32

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: can u help me solve this

And if you still have trouble, here's how I would solve it:

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