Write an eqution that can be used to find h the number of hours in d days

The area of a rectangle is 54x^9y^8 square yards. if the length of the rectangle is 6x^3y^4 yards, which expression represents the width of the rectangle in yards

If x is 6, then 7x= a. 13 b. 42 c. 42x d. 76

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?