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If log 8 (3x) +5 = log 8 (26), what is the value of x?

User Pathogen
by
4.7k points

2 Answers

4 votes

x = 0.0002644

Explanation:


\log _(8)3x + 5 = \log_(8)26\\

We want get the logs on the same side


\log _(8)3x-\log_(8)26=-5\\

When you subtract logs with the same base, the insides get divided


\log_(8)(3x)/(26) =-5

If
\log_(8)x=2\\x = 8^2\\x = 64

We have to do the same here


(3x)/(26) =8^-^5\\(3x)/(26)=(1)/(8^5)\\(3x)/(26)=(1)/(32768)\\\\3x = (26)/(32768)\\x=(26)/(32768*3)\\x=(13)/(49152) = 0.0002644

User Lezir Opav
by
5.0k points
3 votes

Answer:

x=7

Explanation:

3x+5=26

3x=21

x=7