SOLUTION: solve 8^3x-3=4^3x-4

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Question 1037200: solve 8^3x-3=4^3x-4
Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
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solve 8^3x-3=4^3x-4
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8%5E%283x-3%29 = 4%5E%283x-4%29.

Write both sides with the base "2" using 8 = 2%5E3  and  4 = 2%5E2. You will get

2%5E%283%2A%283x-3%29%29 = 2%5E%282%2A%283x-4%29%29.

Since the base are equal, the indexes are equal too:

3*(3x-3) = 2*(3x-4).

Simplify and solve it for x.

By the way, here is how to write correctly your equation when posting to this site:

8^(3x-3) = 4^(3x-4).

Use it when you will be posting next time.