[QUOTE=yamna]OK so this time I am really trying to solve themm but I don't know how to.. I have couple of solutions but I don't think eighter of them is right:
25^x=18
log 25^x=log 18
xlog25= log 18
x=log 18/log 25
x=log 18-25
x=log (-7)
but actually I am not supposed to solve it.. I am just suppose to convert it to expnential if its in lorigmathic form... and its in lorigmathic form I have to convert it to expoenential...
is it suppose to be like:
log(base 25) 18= x??
2. log(base 2)128
so I have no idea how to solve itt.. I tried it with the change base formula but its not working that wayyyy...
THANXX... I HAVE GOT THE ASNWER... I CHATTTED WITH THIS GUY (Capuchin)ON MSN.. AND HE GAVE ME ALL THE DIRECTIONS AND HOW TO APPROCH MY ANSWER :
so it's 25^x = 18
log(25) both sides
so log(25)25^x = log(25)18
log(25)25^x = x
so you can simplify that
and you get what you stated
log(25)18 = x
log(base 2)128
learn to read that question as "what power to i have to raise 2 to to get 128?"
2^x = 128
2, 4, 8, 16, 32, 64, 128
so it's 7
(Edited by Capuchin for clarity)
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