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The difference of the two angles is 180 degrees
buratinogigle   0
Apr 16, 2025
Source: VN Math Olympiad For High School Students P10 - 2025
In triangle $ABC$, let $D$ be the midpoint of $AB$, and $E$ the midpoint of $CD$. Suppose $\angle ACD = 2\angle DEB$. Prove that
\[ 2\angle AED-\angle DCB =180^\circ. \]
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buratinogigle
Apr 16, 2025
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The difference of the two angles is 180 degrees
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Source: VN Math Olympiad For High School Students P10 - 2025
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buratinogigle
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buratinogigle
#1 h  Apr 16, 2025, 1:38 AM
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In triangle $ABC$, let $D$ be the midpoint of $AB$, and $E$ the midpoint of $CD$. Suppose $\angle ACD = 2\angle DEB$. Prove that
\[ 2\angle AED-\angle DCB =180^\circ. \]
This post has been edited 1 time. Last edited by buratinogigle, Apr 17, 2025, 12:11 AM
Reason: Typo
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