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How to solve this equation. watch

1. Hello. I was looking through an AQA GCSE past paper and the last question on the paper was this:

Solve

I was wondering if someone could explain the process of solving an equation like this.
2. can you write the right hand side so that is also has a base of 3?
3. (Original post by xy_)
Hello. I was looking through an AQA GCSE past paper and the last question on the paper was this:

Solve

I was wondering if someone could explain the process of solving an equation like this.
If you have two numbers, like 5^a and 5^b and they are equal (5^a = 5^b) then what can you say about a and b?

And how does this relate to your example, and how is it different?
4. .
5. (Original post by xy_)
Hello. I was looking through an AQA GCSE past paper and the last question on the paper was this:

Solve

I was wondering if someone could explain the process of solving an equation like this.

aren't these exponential equations?
6. Ah, I see. So:

Thanks for the help - if the above is correct then it all makes much more sense!
7. (Original post by SeanFM)
If you have two numbers, like 5^a and 5^b and they are equal (5^a = 5^b) then what can you say about a and b?

And how does this relate to your example, and how is it different?
So a and b must be the same? So getting the same base means the exponents equal each other. So then with the same base I can divide by the base and just solve the equation left by the exponents.
8. (Original post by xy_)
So a and b must be the same? So getting the same base means the exponents equal each other. So then with the same base I can divide by the base and just solve the equation left by the exponents.
Almost correct - just to be pernickety, you can't 'divide' by the base - they disappear as you 'compare' the exponents as they must be equal, like you've said . but well done for figuring out so much from just one small hint

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