Let

x = the present age of Freddy

y = the present age of Lorena

x > y

Six years ago, Freddy was twice the age of Lorena:

x - 6 = 2*(y - 6)

Now the sum of their ages is 45:

x + y = 45

We have the following system of equations:

x - 6 = 2*(y - 6)

x + y = 45

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x = 28 years

y = 17 years

28 - 17 = 9 years

Freddy is 9 years older than Lorena.