log base 4 of (x – 6) + log base 4 of x = 2
=>log base 4 of x(x – 6) = log base 4 of 4^2
=> x(x-6) = 16
=> x^2-6x-16 = (x-8)(x+2) = 0
x = 8, -2(rejected)
Answer: x = 8
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Attn: The domain of log x is x > 0.
use log rule
that says loga +logb=log(ab)
iff the logs have the same base.
then you get
log base 4 (x(x-6))=2
Property of logs
if log base a of b=c
then a^c=b
in your case 4^2=x(x-6)
Simplifying we get
x^2-6x-16=0
(x-8)(x+2)=0
so x=8 or x=-2
NOT FINISHED YET!
Plug both in to see if they work.
x=-2 will NOT work since log base 4 of -2
is UNDEFINED DUE TO THE FACT THE IMPUTS
OF A LOG HAVE TO BE STRICTLY GREATER THAN
0
enjoy