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1990 IMO Longlists
97
Prove that AB = CD = EF - ILL 1990 USA4
Prove that AB = CD = EF - ILL 1990 USA4
Source:
September 19, 2010
geometry proposed
geometry
Problem Statement
In convex hexagon
A
B
C
D
E
F
ABCDEF
A
BC
D
EF
, we know that
∠
B
C
A
=
∠
D
E
C
=
∠
A
F
B
=
∠
C
B
D
=
∠
E
D
F
.
\angle BCA = \angle DEC = \angle AFB = \angle CBD = \angle EDF.
∠
BC
A
=
∠
D
EC
=
∠
A
FB
=
∠
CB
D
=
∠
E
D
F
.
Prove that
A
B
=
C
D
=
E
F
.
AB = CD = EF.
A
B
=
C
D
=
EF
.
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