SOLUTION: 3^4x-7 = 1/9

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Question 187156: 3^4x-7 = 1/9
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
3%5E%284x-7%29+=+1%2F9

We notice that 9 can be written as 3%5E2
So we have 

3%5E%284x-7%29+=+1%2F%283%5E2%29

Now 1%2F%283%5E2%29 can be written as 3%5E%28-2%29
So we have

3%5E%284x-7%29+=+3%5E%28-2%29

Now we can equate the exponents because the bases
are equal, positive, and %22%22%3C%3E1.
So we have

4x-7=-2
4x=5
x=5%2F4

Edwin