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# Indices Question Watch

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1. Hi,

I'm struggling on this question, any advice would be appreciated (working included):

Solve y:

(9^y)/(27^2y+1) = 81

((3^2)^y)/((3^3)^2y+1) = 3^4

(3^2y)/(3^6y+3) = 3^4

2y/(6y+3) = 4

2y = 4(6y+3)
2y = 24y + 12
22y = 12
y = 12/22
y = 6/11

But I know the answer to be y= -7/4. Any help would be much appreciated, I've been at this problem for ages!
2. (Original post by AndINeedHelp)
2y/(6y+3) = 4
What did you do here?
3. (Original post by AndINeedHelp)
Hi,

I'm struggling on this question, any advice would be appreciated (working included):

Solve y:

(9^y)/(27^2y+1) = 81

((3^2)^y)/((3^3)^2y+1) = 3^4

(3^2y)/(3^6y+3) = 3^4

2y/(6y+3) = 4

Incorrect. Should be as you subtract the indices when bases are identical.

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