Both of the cars has traveled in a right angle triangular direction apposite to each other having base 4 and perpendicular 3
Solving it by Pythagoras theorem
hypotenuse^2 = base^2 + perpendicular^2
H^2 = 4^2 + 3^2 = 16+9 = 25
H = 5
The hypotenuse H will be the minimum distance from both the end points to start point
the distance between both end points will be twice of H that is 10 miles.
Answer 10 miles.
