9. (6 points) The sum of the ages of A and B this year is 43 years old. In 4 years, A will be 3 years older than B. A is $\qquad$ years old this year.
【Answer】Solution: According to the sum and difference formula, we get:
Jia's age this year is: $(43+3) \div 2=23$ (years old).
Answer: Jia is 23 years old this year.
Therefore, the answer is: 23.