Answer: Justin is 9 years old, Peyton is 6 years old and Matt is 24 years old
Step-by-step explanation: Let the age of Justin be x years .
And Peyton is three years younger than Justin, therefore Peyton age is
(x-3) years
And Matt is four times as old as Peyton, therefore Matt age is
4(x-3) years
And it is given that
x + x - 3 + 4 (x - 3) = 39
x + x - 3 + 4x - 12 = 39
6x - 15 = 39
6x = 54
x = 9
Therefore , Justin is 9 years old, Peyton is 6 years old and Matt is 24 years old .