There are some instances when an abbreviated form of the distance formula can be used. What is the abbreviated formula and under what conditions can it be used? I will give brainliest to the first correct answer!

Every weekday, mr. jones bikes from his home to his job. sometimes he rides along two roads, the long route that is shown by the solid lines. other times, he takes the shortcut shown by the dashed line. how many fewer kilometers does mr. jones bike when he takes the shortcut instead of the long route?