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    How do you get 3125 to be 25 in this question? 25^2=3125^(x+5)
    I need to make it 25 so both sides have a 25. I know I can divide 3125 by 125 to get it to equal 25 but what number would I put in the power?
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    (Original post by Airess3)
    How do you get 3125 to be 25 in this question? 25^2=3125^(x+5)
    I need to make it 25 so both sides have a 25. I know I can divide 3125 by 125 to get it to equal 25 but what number would I put in the power?
    I would express both 25 and 3125 as powers of 5.

    Once you have 3125 as a power of 5, say 3125 = 5^a then  3125^{x+5} = (5^a)^{x+5} so which rule of indices do you use?
 
 
 
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