Question 570159
<pre>           {{{drawing(200,800/7,-2,26,-2,14, red(line(0,0,23,0),line(23,0,23,12),line(23,12,0,12),line(0,12,0,0),line(0,0,23,12),line(0,12,23,0)),
circle(23/2,6,.5),locate(0-.3,0,A), locate(23-.3,0,B), locate(0-.3,13.9,D),locate(23-.3,13.9,C), locate(23/2-.3,9,E)



 )}}}

The diagonals of a rectangle have equal lengths. Since AC has a length of 28,
and AC is a diagonal, the other diagonal BD also has a length of 28.

The diagonals of a rectangle also bisect each other.  So diagonal BD is
bisected by the other diagonal AC at point E.  And since diagonal BD has
a length of 28 then BE and ED both have a length which is {{{1/2}}} of 28,
or 14 each.

Answer: ED has a length of 14.

Edwin</pre>