Question 833497
You have a property of log like this : if the base of two log are the same, you have log(x) - Log(y) = Log (x/y) 
By the way if the base is 10, you don't need to write the base, it's a rule in Math :) 
So your question is: 
log(y) = 0.7 + 2log(x) 
You have another property you need to use here, it says {{{a*log(x) = log(x^a)}}}
So your equation becomes
{{{log(y) = 0.7 + log(x^2)}}}
{{{log(y) - log(x^2) = 0.7}}}
{{{log(y/(x^2)) = 0.7}}}
The base is 10, so you have
{{{y/(x^2) = 10^(0.7)}}}
{{{y = 10^(0.7)*(x^2)}}}
TA-DAH
:D