1. We start by identifying the problem: explain every step in exercise 9 and 10. 2. Since the exercises are not fully specified, I'll assume exercise 9 and 10 involve typical algebraic operations such as solving equations or simplifying expressions. 3. For each exercise, clearly state the problem, show intermediate steps, and explain each step thoroughly. 4. If you provide the exact content of exercise 9 and 10, I can give detailed, step-by-step solutions explaining all intermediate work. 5. Please share the problem statements or expressions for exercises 9 and 10 for precise assistance.