Find the value of x for the side of a kite

Itook a better photo of the question so y’all can see it i hope it’s a fine photo

Which expression gives you the distance between the points (5,1)and(9,-6)

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?