Question

A bus and a car leave from the same city traveling in opposite directions. The bus leaves 2 hours before the car does. The bus travels at a steady speed of 50 mph while the car travels at 70 mph. After how many hours will the bus and car be 800 miles apart?
If h represents the number of hours the bus travels, then which of the following expressions represents the number of miles the car travels?

Answer 1

number of hours = h

 the bus left 2 hours before the car so the car traveled h-2 hours

The car travels at 70 mph. 

so the equation for the car is: 70(h-2)

Answer 2

Answer:

Car and bus will be 800 miles apart after 7.83 hours.

Expression that represents the distance cover by car will be 70(h - 2) miles

Step-by-step explanation:

Bus travels at a constant speed of 50 mph and the car travels with a speed = 70 mph in the opposite directions.

If the bus travels for h hours then the distance traveled by the bus will be

Distance = Speed × Time

              = 50h

Now we know car starts traveling after 2 hours so total time to travel will be (h - 2) hours.

Therefore, Distance = Speed × Time

Distance covered by car = 70(h - 2) miles

Since they are traveling in the opposite directions so total distance covered will be = Distance covered by bus + Distance covered by car

800 = 50h + 70(h - 2)

800 = 50h + 70h - 140

120h = 800 + 140

120h = 940

h = $\frac{940}{120}$

h = 7.83 miles

Therefore, Car and bus will be 800 miles apart after 7.83 hours.