Velocity, distance and time:
This question is solved using the following formula:

In which v is the velocity, d is the distance, and t is the time.
On the first day of travel, a driver was going at a speed of 40 mph.
Time
, distance of
, v = 40. So


The next day, he increased the speed to 60 mph. If he drove 2 more hours on the first day and traveled 20 more miles
On the second day, the velocity is
.
On the first day, he drove 2 more hours, which means that for the second day, the time is: 
On the first day, he traveled 20 more miles, which means that for the second day, the distance is: 
Thus


System of equations:
Now, from the two equations, a system of equations can be built. So


Find the total distance traveled in the two days:
We solve the system of equation for
, which gets the distance on the first day. The distance on the second day is
, and the total distance is:

From the first equation:


Replacing in the second equation:








Thus, the total distance is:

The total distance traveled in two days was of 380 miles.
For the relation between velocity, distance and time, you can take a look here: brainly.com/question/14307500