The movie theater is at (1,6) and the park is at (5,1). What is the shortest distance from the movie theater to the park

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.

The answer simplified would be. -6300x

What am i doing here. add?