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39
Find measure of angle CDE
Find measure of angle CDE
Source:
October 12, 2010
geometry
geometry unsolved
Problem Statement
Let
A
B
C
ABC
A
BC
be an isosceles triangle,
A
B
=
A
C
,
∠
A
=
2
0
∘
AB = AC, \angle A = 20^{\circ}
A
B
=
A
C
,
∠
A
=
2
0
∘
. Let
D
D
D
be a point on
A
B
AB
A
B
, and
E
E
E
a point on
A
C
AC
A
C
such that
∠
A
C
D
=
2
0
∘
\angle ACD = 20^{\circ}
∠
A
C
D
=
2
0
∘
and
∠
A
B
E
=
3
0
∘
\angle ABE = 30^{\circ}
∠
A
BE
=
3
0
∘
. What is the measure of the angle
∠
C
D
E
\angle CDE
∠
C
D
E
?
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