1. The phrase "the first case" usually means solving the first part or condition of a problem. 2. To explain more simply, identify exactly what the first case or scenario is about. 3. Break it down into smaller, easier-to-understand pieces. 4. Use plain language to describe each step without complex terms. 5. If this relates to a math problem, write down the initial expressions or conditions for this case. 6. Show how to simplify or manipulate these expressions step by step. 7. Provide the final simplified result or conclusion for the first case. If you provide the specific problem or the first case you mean, I can give a detailed step-by-step explanation exactly as above!