Amy drove x miles, and Carl drove 71​ less than Amy's distance

Answer 1

The total distance Amy and Carl drove is equal to the sum of their distances. Let x be the distance Amy drove.

Then, Carl drove x - 71 miles.

The total distance they drove is x + (x - 71) = 2x - 71.

Therefore, the total distance they drove is 2x - 71 miles.