1. **State the problem:** Jade is twice as old as Sara. If Sara is $y$ years old, find an expression for Jade's age. 2. **Understand the relationship:** "Twice as old" means Jade's age is 2 times Sara's age. 3. **Write the formula:** If Sara's age is $y$, then Jade's age is $2 \times y$. 4. **Express the answer:** The expression representing Jade's age is $$2y$$. 5. **Check other options:** - $y^2$ means Sara's age squared, which is not correct. - $y + 2$ means 2 years older, not twice as old. - $\frac{y}{2}$ means half Sara's age, which is incorrect. **Final answer:** The correct expression is $2y$.