A Cessna 172 pilot reported an NMAC while approaching a non-towered airport to land.

Narrative

I was flying a passenger from ZZZ to the city. After spending around a half hour of flight around the area; I decided to fly both of us back to ZZZ for a full stop landing; and began to complete all of the required checklists and descent procedures beforehand. We flew along a major road that led into a town and buildings that would set us up for a 45 degree entry for a left downwind pattern for Runway XX. I was flying a slow descent rate until reaching 2300 ft MSL and completing the required checklists; as well as looking outside the cockpit periodically and making position reports. Upon reaching the buildings; my passenger noticed traffic below us and on our right side; and I immediately noticed that another aircraft was pretty close to our position. We were both flying opposite directions and; remaining at the same altitudes; no abrupt/evasive action was needed to avoid the other aircraft. I think I should have utilized a better scanning technique in that moment; as I was quickly scanning the outside environment while completing checklists and configuring the aircraft for landing. It is extremely important to utilize the 10 degree interval and one second scanning technique; as well as a great sense of one's outside environment; while operating an aircraft; so that other forms of obstacles and traffic can be quickly spotted and a plan of action can be taken to avoid them. I also could have decided to remain at a select altitude until reaching ZZZ; so each aircraft could have had a bigger clearance between each other.