log[3](2x + 8) + log[3](3x) = log[2] (3)^2
rule: use log[b] x^n = n log[b] x
log[3](2x + 8) + log[3](3x) = 2 log[2] 3
rule: use log [b] a = 1/(log [a] b)
log[3](2x + 8) + log[3](3x) = 1/(2 log[3] 2)
I expanded and got as far as I can... hope this helps