∴AB=BC, ∠ BAC = ∠ BCA = 6. (1 point)
∵ Quadrilateral ACDE is an isosceles trapezoid, ∠ EAC = 6.
that is, ∠BAE=∠BCD. (2 points)
In △ABE and △BCD, AB=BC, ∠ BAE = ∠ BCD, AE=CD,
∴△ Abe ≌. (6 points)
(3) From (2),
ANCN=
ABCD=2,
∴CN=
12AN=
13AC, (8 points)
similarly AM=
13AC.
∴∠ DCF = 6. (1o points)
In Rt△CDF, ∴∠ CDF = 3,
∴CF=
12CD=
12, < p. (11 points)
In Rt△BDF, ∵BF=BC+CF=2+
12=
52, DF=
32, < P > ∴ BD = < P > BF2+DF2 = < P > (.