x = Tom's age
x + 14= Joe's age
3x = Rob's age
x + (x + 14) + 3x = 64
Let's combine like terms
5x + 14 = 64
Subtract 14 from both sides
5x = 50
Divide each side by 5
x = 10
Tom is 10 years old.
Joe's age = 10 + 14 = 24 years old
Rob's age = 3(10) = 30 years old