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# :S watch

1. 4^x= 8^2-x
2. Is that (8^2) - x or is it 8^(2-x)?
3. 8^(2-x)
4. split it into factors of 2, as it is the Lowest common multiple

4 = 2^2

8 = 2^3

Therefore the equation can be written as 2^(2x) = 2^(3(2-x))
5. (Original post by Byrney11)
4^x= 8^2-x

When you get questions like these, and the big numbers (base numbers, ie 4 and 8) aren't the same, the first thing you should aim to do is to make the big numbers the same by rewriting them.

For example, 9 can be written as , so can be written as

If you had
, which is the same as writing due to that mutiplication rule of indices, you can equate the indices: 2x = x+1 and solve from there.

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