Exponents: If 25^(x-1) = 5^(2x-1) - 100, find value of x

lPing7

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If 25^(x-1) = 5^(2x-1) - 100, find value of x
Now I can make this:
5^(2x-2) = 5^(2x-1) - (2^2 * 5^2)
How do I continue further?
Thanks in advance

P.S Hope question is clear unlike previous ones
 
Last edited by a moderator:
If 25^(x-1) = 5^(2x-1) - 100, find value of x
Now I can make this:
5^(2x-2) = 5^(2x-1) - (2^2 * 5^2)
How do I continue further?
Thanks in advance

P.S Hope question is clear unlike previous ones
5^(2x-2) = 5^(2x) * 5^(-2)

ln(5^(2x)) = 2x ln(5)
EDIT: But you probably won't need to do that if you work it out.
 
Last edited:
If 25^(x-1) = 5^(2x-1) - 100, find value of x
Now I can make this:
5^(2x-2) = 5^(2x-1) - (2^2 * 5^2)
How do I continue further?
Thanks in advance

P.S Hope question is clear unlike previous ones

25^(x-1) = 5^(2x-1) - 100

52x-2 = 52x-1 - 100

1/25 * 52x = 1/5 * 52x - 100

52x = 5 * 52x - 2500

4 * 52x = 2500

Continue.....
 
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