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If (x  3)^2 = 225, which of the following could be the
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24 Feb 2013, 16:57
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Re: If (x  3)^2 = 225, which of the following could be
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24 Feb 2013, 21:03
carcass wrote: If \((x  3)^2 = 225\), which of the following could be the value of \(x + 3\) ? (A) 15 (B) 12 (C) 9 (D) 15 (E) 18 in this question if we take the square of both sides we have\(x  3= 15\)so why the explanation says: \(x  3 = 15\) and \(x  3 = 15\) ????? Honestly carcass, that's a newbie mistake and you should not be making it! \((x  3)^2 = 15^2\) When you take the root, you get x3 = 15 and hence you get x = 18 or 12 Alternatively, \((x  3)^2  15^2 = 0\) (x  3  15)(x  3 + 15) = 0 x = 18 or 12
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Re: If (x  3)^2 = 225, which of the following could be
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24 Feb 2013, 18:14
carcass wrote: If \((x  3)^2 = 225\), which of the following could be the value of \(x + 3\) ? (A) 15 (B) 12 (C) 9 (D) 15 (E) 18 in this question if we take the square of both sides we have\(x  3= 15\)so why the explanation says: \(x  3 = 15\) and \(x  3 = 15\) ????? both 18 and 12 satisfy the given equation Posted from my mobile device



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Re: If (x  3)^2 = 225, which of the following could be
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24 Feb 2013, 18:23
jbisht wrote: carcass wrote: If \((x  3)^2 = 225\), which of the following could be the value of \(x + 3\) ? (A) 15 (B) 12 (C) 9 (D) 15 (E) 18 in this question if we take the square of both sides we have\(x  3= 15\)so why the explanation says: \(x  3 = 15\) and \(x  3 = 15\) ????? both 18 and 12 satisfy the given equation Posted from my mobile device hence, x+3 is 21 or 9 Posted from my mobile device



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Re: If (x  3)^2 = 225, which of the following could be
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24 Feb 2013, 19:01



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Re: If (x  3)^2 = 225, which of the following could be
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24 Feb 2013, 19:44
carcass wrote: If \((x  3)^2 = 225\), which of the following could be the value of \(x + 3\) ? (A) 15 (B) 12 (C) 9 (D) 15 (E) 18 in this question if we take the square of both sides we have\(x  3= 15\)so why the explanation says: \(x  3 = 15\) and \(x  3 = 15\) ????? Yes here are my two cents... \((x  3)^2 = 225\) Since squaring on both sides leaves +/ \(x  3 = +/ 15\) This gives two eqns.. \(x  3 = 15\) \(x  3 = 15\) So, x= 18 means x+3=15 or x=12 means x+3=9
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Re: If (x  3)^2 = 225, which of the following could be
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25 Feb 2013, 02:46
VeritasPrepKarishma wrote: carcass wrote: If \((x  3)^2 = 225\), which of the following could be the value of \(x + 3\) ? (A) 15 (B) 12 (C) 9 (D) 15 (E) 18 in this question if we take the square of both sides we have\(x  3= 15\)so why the explanation says: \(x  3 = 15\) and \(x  3 = 15\) ????? Honestly carcass, that's a newbie mistake and you should not be making it! \((x  3)^2 = 15^2\) When you take the root, you get x3 = 15 and hence you get x = 18 or 12 Alternatively, \((x  3)^2  15^2 = 0\) (x  3  15)(x  3 + 15) = 0 x = 18 or 12 No no .......you are perfectly right . maybe tired maybe stressed..........I know but you are right. Thanks
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Re: If (x  3)^2 = 225, which of the following could be the
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27 Feb 2014, 20:16
One more method (This is time consuming) Writing the equation as x^2  6x + 9  225 = 0 x^2  6x + 9  216 = 0 (x18) . (x+12) = 0 x = 18 OR x = 12 x+3=15 or x+3 = 9
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Re: If (x  3)^2 = 225, which of the following could be the
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If (x  3)^2 = 225, which of the following could be the
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Updated on: 03 Nov 2016, 06:13
x3 = 15
or
x3= 15So x=18 or x=12 x+3=21 or x+3=9 So Answer B
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Originally posted by AnisMURR on 03 Nov 2016, 03:48.
Last edited by AnisMURR on 03 Nov 2016, 06:13, edited 1 time in total.



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Re: If (x  3)^2 = 225, which of the following could be the
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03 Nov 2016, 04:05
How we can confirm which answer to be considered? Sent from my Redmi Note 3 using GMAT Club Forum mobile app



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If (x  3)^2 = 225, which of the following could be the
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03 Nov 2016, 04:15
Pm091989 wrote: How we can confirm which answer to be considered? Sent from my Redmi Note 3 using GMAT Club Forum mobile app(x3)^2= 225 (x3)^2= 15^2 (x3)= +15 or 15 x=18 or 12 now the question asks which could be the value of x+3 if x=18 ==> x+3=21 (could be) if x=12==> x+3= 9 (could be) only9 is available as an option. If both 9 and 21 were available as individual options then the question would be wrong.



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Re: If (x  3)^2 = 225, which of the following could be the
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03 Nov 2016, 11:33
carcass wrote: If (x  3)^2 = 225, which of the following could be the value of x + 3 ? (A) 15 (B) 12 (C) 9 (D) 15 (E) 18 in this question if we take the square of both sides we have\(x  3= 15\)so why the explanation says: \(x  3 = 15\) and \(x  3 = 15\) ????? \(\sqrt{(x  3)^2} = \sqrt{225}\) Or, \(( x  3 ) =\) + \(15\) If x = +15 x  3 = 15 Or, x = 18 so x + 3 = 21 If x  3 =  15 Or, x = 12 , so x + 3 = 9Hence, answer will be (C) 9
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Re: If (x  3)^2 = 225, which of the following could be the
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04 Nov 2016, 16:18
carcass wrote: If (x  3)^2 = 225, which of the following could be the value of x + 3 ?
(A) 15 (B) 12 (C) 9 (D) 15 (E) 18 We can start by taking the square root of both sides of the equation (x  3)^2 = 225. √(x  3)^2 = √225 x  3 = 15 or x  3 = 15 Thus, x = 18 or 12. So possible values of x + 3 are as follows: 18 + 3 = 21 12 + 3 = 9 Since 9 is the only answer within the answer choices, the answer is C. Answer: C
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Re: If (x  3)^2 = 225, which of the following could be the
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04 Nov 2016, 22:28
carcass wrote: If (x  3)^2 = 225, which of the following could be the value of x + 3 ?
(A) 15 (B) 12 (C) 9 (D) 15 (E) 18
(x  3)^2 = 225 i.e. x3 = +15 or 15 i.e. x = +18 or 12 i.e. x+3 = +21 or 9 Answer: option C
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