If a – b = 3 and a² + b² = 29, find the value of ab:

A. 10
B. 14
C. 18
D. 20

🧠 Explanation (Math):

Given: a − b = 3 and a² + b² = 29; find ab
Step 1: Use identity (a − b)² = a² + b² − 2ab
Step 2: Substitute: 3² = 29 − 2ab ⇒ 9 = 29 − 2ab
Step 3: 2ab = 20 ⇒ ab = 10
Final Answer: 10