I missed a whole week of math class and I'm totally lost. I learn best through examples and working my way back from answers through trial and error.

how would I solve for logx16 = 2/3 (with x being the base)... I rewrote it as X^2/3 = 16 but don't know where to go from there... Thanks in advance, I'm sure this is a really simple answer.

And, log(base x)(1/81)=-4