Here are a few tips on where a TV should be placed in a living room:
Check if the TV is placed closest to the power source.
Place the TV at your eye level so that your eyes or neck doesn't get strained while watching.
Place it in the center of the seating area if TV is your focal point.
Incorporate your TV into your decor by placing it on a bookcase and surrounding it with other things such as books, objects, etc.