You are visiting Chicago and need to take a taxi. The taxi fare is $3.25 plus $1.80 for each mile travelled. You also want to tip the driver $2. You only have $20 in your pocket. How many miles can you travel without going over $20? Write an equation you can use to solve the problem. Define your variable. (Tell me what the variable in your equation represents.) Explain how you arrived at your equation and how it models the problem. Finally, explain how to solve the equation and what the solution is.