SOLUTION: 5=4^x

Algebra ->  Square-cubic-other-roots -> SOLUTION: 5=4^x      Log On


   

Question 198101: 5=4^x
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
5=4%5Ex
Take the log to the base 10 of both sides
log%285%29+=+log%284%5Ex%29
Note the general rule:
log%28a%5Eb%29+=+b%2Alog%28a%29, so
log%285%29+=+x%2Alog%284%29
x+=+log%285%29%2Flog%284%29
x+=+.69897%2F.60206
x+=+1.161
I can check the answer with my calculator
5+=+4%5E1.161
5+=+4.99999995 (error due to rounding)
OK