Please help solving the following logarithm: 8^(x-9) = 19^(3x+2)
So far, I have log8^(x-9) = log19^(3x+2) (x-9)log8 = (3x+2)log19
so far so good. :) Next step = distribute log(8) over (x-9) and distribute log(19) to (3x+2).
ok...got that...xlog8-9log8 = 3xlog19 + 2log19
i always miss it at this step.
Hint -- it's best to put parenthesis around log(number). log is a function, and the number is the input or independent variable. :) Ok, so the next step here is to "get all the xs on one side" and "get all the log(number) on the other."
(3xlog19-xlog8) = (9log8-2log19) ???
Yes. Only thing, use parenthesis around the log of the number... (3xlog(19)-xlog(8)) = (9log(8)-2log(19)) instead of (3xlog19-xlog8) = (9log8-2log19) This is because log(19), log(8) -- pronounced "Log of 19", "log of 8" etc... are numbers. So they are just the same as... if you like, 2 or 3. In the sense they are numbers or constants. Ok, next step -- factor out the x from the expression on the left. (3xlog(19)-xlog(8)) = ?? (factor out the x)
x(3log(19) - log(8))
Yup! Now that is still equal to (9log(8)-2log(19)) So you now have x(3log(19) - log(8)) = (9log(8)-2log(19)) It's important to keep in mind that 3log(19) is just a number, as is log(8). So their difference is just a number, it's sort of like saying... x*4 = (9log(8)-2log(19)) What would you do next?
diviide
Yup. :) The final answer will be a big fraction with logs in the numerator and denominator.
i divided 9log(8)-2log(19) on both sides, is that correct
i'm confusing myslef all over again
is the answer x=2log(19)+9log(8)/3log(19)-log8
are you still there?
thank you
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