Can you get a ticket for slower driving if driving 55 from mesquite Nevada to beaver dam on interstate 15 in Arizona if beaver dam Arizona is 8 miles from mesquite Nevada and speed is 75?

In Texas you can be ticketed for driving too slow. But, it's rare unless a minimum speed is posted. When you go dangerously slow such that you are impeding traffic and cars are stacking up behind you they can ticket you for reckless driving but this is rare. If you are driving slower then the speed limit you should stay in the right lane unless turning left or passing a slower vehicle. In any event, 55 mph doesn't seem like an unreasonably slow speed, so you're probably all right.