Using New Quizzes/Math Quill to write questions for my geometry courses and I cannot find a way to get the line symbol above my letters. I am NOT looking for \overline{AB}, as that produces a bar with no arrows. I have tried searching various Latex codes and \overleftrightarrow is what I am looking for, however this does not work in New Quizzes. I do not understand why all Latex code isn't supported in MathQuill. 

This is really frustrating as a Geometry teacher. My workaround is \overleftarrow{A}\overrightarrow{B} which is so cumbersome. Anyone know the code for what I'm looking for? And if not, please add it in!