How do you solve the equation log3(x+5)log3(x7)=2?

1 Answer
Feb 17, 2015

You can use the following facts:

logaMlogaN=log(MN) and:

logab=xax=b

So you get:

log3(x+5)log3(x7)=2
log3(x+5x7)=2
x+5x7=32
x+5=9(x7)
x9x=635
8x=68
x=688=172