Question 820003
------------

2logx   log5 = log15   log2x
logx^2   log5 = log15   log2x
logx^2 - log2x = log15 - log5
--------------

From law of log: LogA_c - LogB_c = Log_c (A/B)

:. Log x^2/2x = Log 15/5
Log x/2 = Log 3

Log with Log cancel:
x/2 = 3
x = 6