In the quadrilateral \(ABCD\) the
diagonals \(AC\) and \(BD\) intersect at the point \(E\). It is known that the perimeter of the
triangle \(ABC\) is equal to the
perimeter of the triangle \(ABD\), and
the perimeter of the triangle \(ACD\)
equals the perimeter of the triangle \(BCD\).
Prove that \(AE=BE\).