1. **State the problem:** An automobile salesman makes 100 plus a 2% commission on the sale price of a car. We want to find the minimum sale price of a car so that the salesman makes at least 800. 2. **Write the formula:** The total earnings $E$ from selling a car priced at $P$ is given by: $$E = 100 + 0.02P$$ 3. **Set up the inequality:** Since the salesman wants to make at least 800, we write: $$100 + 0.02P \geq 800$$ 4. **Solve the inequality:** Subtract 100 from both sides: $$\cancel{100} + 0.02P - \cancel{100} \geq 800 - 100$$ $$0.02P \geq 700$$ Divide both sides by 0.02: $$\frac{0.02P}{\cancel{0.02}} \geq \frac{700}{\cancel{0.02}}$$ $$P \geq 35000$$ 5. **Interpretation:** The sale price of the car must be at least 35000 for the salesman to make 800 or more. **Final answer:** $$\boxed{35000}$$