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CMIMC Problems
2021 CMIMC
2.3
2.3
Part of
2021 CMIMC
Problems
(1)
2021 Geo Div 2 P3
Source:
3/2/2021
Consider trapezoid
[
A
B
C
D
]
[ABCD]
[
A
BC
D
]
which has
A
B
∥
C
D
AB\parallel CD
A
B
∥
C
D
with
A
B
=
5
AB = 5
A
B
=
5
and
C
D
=
9
CD = 9
C
D
=
9
. Moreover,
∠
C
=
1
5
∘
\angle C = 15^\circ
∠
C
=
1
5
∘
and
∠
D
=
7
5
∘
\angle D = 75^\circ
∠
D
=
7
5
∘
. Let
M
1
M_1
M
1
be the midpoint of
A
B
AB
A
B
and
M
2
M_2
M
2
be the midpoint of
C
D
CD
C
D
. What is the distance
M
1
M
2
M_1M_2
M
1
M
2
?Proposed by Daniel Li
geometry