Answer:Let's simplify the expressions: 1. 18x + 16x - 4x - 5x + 15 - Combine like terms: (18 + 16 - 4 - 5)x + 15- Simplify: 25x + 15 Therefore, the simplified expression is 25x + 15 2. 2x + 3 - This expression is already in its simplest form. Therefore, the simplified expression is 2x + 3Step-by-step explanation:The answer is 2x + 3