One morning, Alex decided to visit a friend. He left his house at $7$ AM, drove at a constant speed of $50$ miles per hour, and arrived at his friend's house at $9$ AM. After visiting for $2$ hours, Alex drove home at a constant speed of $40$ miles per hour. Which of the following graphs best illustrates the distance between Alex’s car and his house over the course of his trip? Assume the x-axis represents time in hours, where $7$ corresponds to $7$ AM, $8$ to $8$ AM, and so on.