Question

A truck leaves an intersection going 42 miles per hour. Half an hour later, a car going 62 miles per
hour follows the truck. If x is the time, in hours, required for the car to catch the truck, then which of
the following equations can be used to solve for x?

Answer 1

Not sure about your invisible equations, but mine would be

42x = 62(x - 1/2)

Answer 2

Since x is the amount of time it takes for both vehicles to travel a distance specified. you set those 2 rates equal to each other. In the Problem, it specifies that the starting points for both vehicles are not the same. The Truck has a half an hour head start on the car, and since we know the rate at which the car is traveling. We can find the difference in starting points.
The truck travels 42m/h * .5h = 21m.
42x + 21 = 62x

Answer 3

I FIND IT DIFFICULT