On Monday, Avi walked from his home to the school track and walked 4 laps around the track for a total of 3.5 miles. On Saturday, Avi ran from his home to the school track, ran 2 laps, and then ran home for a total of 4 miles. Let x represent the distance from Avi's home to the school track, and let y represent the distance of one lap around the track. Write a system of equations to represent this situation.

3.5 = x + 4*y

4 = 2x + 2*y

Step-by-step explanation:

The total distance ran by Avi is the sum of the distance from his house to the track, and the total distance ran in the tracks (that is, the distance of one lap times the number of laps Avi ran).

If we call 'd' the total distance and 'k' the number of laps, we have the equation:

d = x + k*y

So with the data given, we can have the following system:

3.5 = x + 4*y

4 = 2x + 2*y

In the second equation, we have 2x because Avi ran from his home to the track, and in the end ran back home, so Avi ran the distance x two times.