Question

If you travel 40 miles east and then turn around and drive 12 miles west, the displacement is?

Answer 1

40-20=20 you would be in the middle of the 2 miles. do the math and you will get your answer the same way that i did.

Answer 2

The answer is 28 miles.

Displacement is not the same as distance. Total distance would be the sum of two distances: 40 + 12 = 52 miles.
However, displacement is the shortest distance from the initial and final position. Take a look at the attached image. Displacement is the difference of two distances:
D = 40 - 12 = 28 miles