How do you solve 5^x = 105x=10?

1 Answer
Feb 24, 2016

x=log_5 10 ~~1.430677x=log5101.430677

Explanation:

Make use of the standard relationship
color(white)("XXX")log_b a = c <=> b^c = aXXXlogba=cbc=a
or (reversed)
color(white)("XXX")b^c=a <=> log_b aXXXbc=alogba

So
color(white)("XXX")5^x= 10 <=> log_5 10 = xXXX5x=10log510=x

log_5 10log510 can be evaluated using a calculator as ~~1.4306771.430677