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If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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Updated on: 30 Jul 2018, 21:23
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If \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})\), what is the value of y in terms of x? A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8
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Originally posted by gsingh0711 on 30 Jul 2018, 15:59.
Last edited by Bunuel on 30 Jul 2018, 21:23, edited 2 times in total.
Renamed the topic and edited the question.



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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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30 Jul 2018, 16:00
Explanation:
3y+1+3y−2+3y−3=85(3x+5)
⇒ 3y(31+3−2+3−3)=85(3x+5)
⇒ 3y(3+19+127)=85(3(x+5)) )
⇒ 3y(8527)=85(3(x+5))
⇒ 3y=27(3x+5)=33×3x+5
⇒ 3y=3x+8
⇒ y = x + 8
Answer: D.
I think, I deserve a kudus LoL



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If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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30 Jul 2018, 21:11
gsingh0711 wrote: If \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Poor question at the first look itself.. All the choices have coefficient of X and y same as y=X or y=X+2 But the two sides tell us that y has 9 as coefficient and X has 85*3, so can never be equal \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)........9y4=255x+425.......9y=255x+429........y=85x/3 + 143/3...\) If it is Question is \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})................... 3^{y3}(3^4+3+1)=85(3^{X+5}................... 3^{y3}*85=85*3^{X+5}...................... 3^{X+5}=3^{y3}\) Equating the powers x+5=y3.......y=x+8 D
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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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30 Jul 2018, 21:24
chetan2u wrote: gsingh0711 wrote: If \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Poor question at the first look itself.. All the choices have coefficient of X and y same as y=X or y=X+2 But the two sides tell us that y has 9 as coefficient and X has 85*3, so can never be equal \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)........9y4=255x+425.......9y=255x+429........y=85x/3 + 143/3...\) Yes. The formatting in the question as well in the "solution" was all messed up. I guess the guy just copy pasted both from some source without checking. I fixed it.
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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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31 Jul 2018, 04:12
Bunuel wrote: chetan2u wrote: gsingh0711 wrote: If \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Poor question at the first look itself.. All the choices have coefficient of X and y same as y=X or y=X+2 But the two sides tell us that y has 9 as coefficient and X has 85*3, so can never be equal \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)........9y4=255x+425.......9y=255x+429........y=85x/3 + 143/3...\) Yes. The formatting in the question as well in the "solution" was all messed up. I guess the guy just copy pasted both from some source without checking. I fixed it. I think system failed the read the raised to the powers and that is why formatting looked messed up.



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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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28 Aug 2018, 03:23
gsingh0711 wrote: If \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Dear Moderator, Found this PS question , in the DS section, hope you will do the needful. Thank you.
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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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28 Aug 2018, 04:59
stne wrote: gsingh0711 wrote: If \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Dear Moderator, Found this PS question , in the DS section, hope you will do the needful. Thank you. ___________________ Done. Thank you.
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If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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28 Aug 2018, 06:30
gsingh0711 wrote: Explanation:
3y+1+3y−2+3y−3=85(3x+5)
⇒ 3y(31+3−2+3−3)=85(3x+5)
⇒ 3y(3+19+127)=85(3(x+5)) )
⇒ 3y(8527)=85(3(x+5))
⇒ 3y=27(3x+5)=33×3x+5
⇒ 3y=3x+8
⇒ y = x + 8
Answer: D.
I think, I deserve a kudus LoL gsingh0711 hey there thank you for your explanation To deserve kudos please make explanation clear and math friendly (explain with words step by step) Use math formatting tools express exponent like this \(3^2\)



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If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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28 Aug 2018, 07:49
chetan2u wrote: gsingh0711 wrote: If \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Poor question at the first look itself.. All the choices have coefficient of X and y same as y=X or y=X+2 But the two sides tell us that y has 9 as coefficient and X has 85*3, so can never be equal \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)........9y4=255x+425.......9y=255x+429........y=85x/3 + 143/3...\) If it is Question is \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})................... 3^{y3}(3^4+3+1)=85(3^{X+5}................... 3^{y3}*85=85*3^{X+5}...................... 3^{X+5}=3^{y3}\) Equating the powers x+5=y3.......y=x+8 D chetan2u can you please explain how from this \(3^{y3}(3^4+3+1)=85(3^{X+5}\) you got this \(3^{y3}*85=85*3^{X+5}\) ? what happened to this \((3^4+3+1)\) ?



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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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28 Aug 2018, 08:04
dave13 wrote: chetan2u wrote: gsingh0711 wrote: If \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 Poor question at the first look itself.. All the choices have coefficient of X and y same as y=X or y=X+2 But the two sides tell us that y has 9 as coefficient and X has 85*3, so can never be equal \(3y + 1 + 3y − 2 + 3y − 3 = 85(3x + 5)........9y4=255x+425.......9y=255x+429........y=85x/3 + 143/3...\) If it is Question is \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})................... 3^{y3}(3^4+3+1)=85(3^{X+5}................... 3^{y3}*85=85*3^{X+5}...................... 3^{X+5}=3^{y3}\) Equating the powers x+5=y3.......y=x+8 D chetan2u can you please explain how from this \(3^{y3}(3^4+3+1)=85(3^{X+5}\) you got this \(3^{y3}*85=85*3^{X+5}\) ? what happened to this \((3^4+3+1)\) ? Hi.. 3^4+3+1=81+3+1=85 So 3^4+3+1 is replaced with 85
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If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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Updated on: 10 Feb 2019, 21:40
\(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})\)
\(3^{y + 1} ( 1 + 3^{− 3} + 3^{− 4}) = (5)(17)(3^{x + 5})\)
\(3^{y + 1} ( 1 + {1/27} + {1/81}) = (5)(17)(3^{x + 5})\)
\(3^{y + 1} ( {85/81}) = (5)(17)(3^{x + 5})\)
\(3^{y + 1} ( 85 * 3^{− 4}) = (85)(3^{x + 5})\)
y + 1 + (  4 ) = x + 5
y = x + 8
D



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If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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10 Feb 2019, 21:31
gsingh0711 wrote: If \(3^{y + 1} + 3^{y − 2} + 3^{y − 3} = 85(3^{x + 5})\), what is the value of y in terms of x?
A. x B. x + 2 C. x − 2 D. x + 8 E. x − 8 \(3^y\) [ 3 + 1/9 +1/27 ] = 85 \((3^{x + 5})\) take \(3^y\) common \(3^y\) [ 85/27] = 85 \((3^{x + 5})\) \(3^y\) = \((3^{x + 8})\) y = x+8 D
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Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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24 Mar 2019, 04:53
3^Y•3 + 3^Y•3^2 + 3^Y•3^3 = 85•3^X•3^5 3^Y ( 3 + 1/9 +1/27) =85•3^5•(3^X) 3^Y (85/27) = 85•3^5•(3^X) 3^Y = 3^3•3^5•3^X Y= 3+5 +X Y = X +8
Answer D




Re: If 3^(y + 1) + 3^(y − 2) + 3^(y − 3) = 85(3^(x + 5), what is the value
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