Question 245741
set it up like this

4m = f
2m + 20 = f

Multiply the top equation by -1 to eliminate to f(represents father's age)

-4m = -f
2m + 20 = f

Add equations together

-2m + 20 = 0
-2m = -20

m = 10

You are 10 years old.
Your father is 40 years old.

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