The building has an endpoint of point A at the top of the building, and an endpoint C at the front door. The building is 19 stories tall. So we know that the length of AC¯¯¯¯¯¯¯¯ is 19 . Chris works at point B on the building which is 5 stories above C . Find the length of AB¯¯¯¯¯¯¯¯ . We will start with the segment addition postulate: AB BC=AC Substitute in what we know AB 5=19 We will subtract 5 from both sides. AB 5−5=19−5 AB= Answer 1 Question 13