SOLUTION: I am getting really frustrated because I don't know how to go about solving this at all. Use log{{{10}}}5 = 0.6990 and log{{{10}}}7 = 0.8451 to evaluate log{{{10}}}0.05 PLEASE walk

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: I am getting really frustrated because I don't know how to go about solving this at all. Use log{{{10}}}5 = 0.6990 and log{{{10}}}7 = 0.8451 to evaluate log{{{10}}}0.05 PLEASE walk      Log On


   



Question 20664: I am getting really frustrated because I don't know how to go about solving this at all. Use log105 = 0.6990 and log107 = 0.8451 to evaluate log100.05 PLEASE walk me through this!!
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
you mean log 5 to base 10=0.6990 etc..since all logs are to base 10 we may take it for granted and drop writing that base..so we have
log 5 = 0.6990
log 7 =0.8451
to find log 0.05
log 0.05=log (5/100)=log 5 - log 100 = 0.6990 - 2 = -1.3010...
since log 100 to base 10 =2...note that 10^2 = 100 ....
hence by definition log 100 to base 10 =2..