Final answer:
Geraldine's age is represented as t - 4, and Steven's age is represented as 2*(t - 4).
Step-by-step explanation:
If Geraldine is 4 years younger than Tom, then we can represent Geraldine's age as:
Geraldine's age = Tom's age - 4
And if Steven is twice as old as Geraldine, we can represent Steven's age as:
Steven's age = 2 * Geraldine's age
So, Geraldine's age is t - 4 and Steven's age is 2*(t - 4).