Answer:
Dave: 36 years old
Matt: 18 years old
Step-by-step explanation:
Dave's age can be expresses as 2x of Matt (which is only x).
If 5 years ago the sum was 44, after this time the sum will be 44 + 5*2(person) = 54
Follow this expression:
2x+x=54
3x=54
x=18
Dave is 2x (36 years old) and Matt is 18 years old.