\"\"

\

The endpoints are \"\" and \"\".

\

The midpoint of a segment with endpoints \"\" is \"\"

\

\"\"              (Substitute  \"\")

\

\"\"                             (Add: \"\")

\

\"\"                               (Divide: \"\")

\

The midpoint is \"\"\"\"

\

The midpoint of the segment with endpoints \"\" and \"\" is \"\".