(NEED HELP ASAP!) Aubrey and Charlie are driving to a city that is 120 mi from their house. They have already traveled 20 mi, and they are driving at a constant rate of 50 mi/h. Complete the function that models the distance they drive as a function of time. Then complete a reasonable domain for this situation.

1. function notation in slope-intercept form: f(x) = ?
2. reasonable domain: ? ≤ x ≤ ?