Economics Help: Computing Demand Functions

**Tom's musical taste is a little weird. He listens to Lady Gaga songs (good 1), and to Arcade Fire tunes (good 2).**

I) Suppose his preferences over music consumption can be described by the utility function: U(x1,x2) = ln(x1) + 2ln(x2)

Compute Tom's demand functions x1(m, p1, p2) and x2(m, p1, p2), respectively. Then, graph his consumption choice for m = 120,

p1 = 2, and p2 = 1 (label everything).

Don't worry about the graphing part. I just don't know ho to get the demand functions of x1 and x2.

Does anybody know how to do get the demand function?

Thanks!