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<DAC+<EBD+<ACE+<BDA+<CEB in covex pentagon (2008 HOMC Junior Q7)
<DAC+<EBD+<ACE+<BDA+<CEB in covex pentagon (2008 HOMC Junior Q7)
Source:
July 18, 2019
geometry
convex
pentagon
angles
Problem Statement
The figure
A
B
C
D
E
ABCDE
A
BC
D
E
is a convex pentagon. Find the sum
∠
D
A
C
+
∠
E
B
D
+
∠
A
C
E
+
∠
B
D
A
+
∠
C
E
B
\angle DAC + \angle EBD +\angle ACE +\angle BDA + \angle CEB
∠
D
A
C
+
∠
EB
D
+
∠
A
CE
+
∠
B
D
A
+
∠
CEB
?
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