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Indonesia Regional MO OSP SMA - geometry
2013.5
2013.5
Part of
Indonesia Regional MO OSP SMA - geometry
Problems
(1)
< ABC <= 60^o if longest altitude AD=median BE
Source: 2013 Indonesia MO Province P2 q5 OSP
12/10/2020
Given an acute triangle
A
B
C
ABC
A
BC
. The longest line of altitude is the one from vertex
A
A
A
perpendicular to
B
C
BC
BC
, and it's length is equal to the length of the median of vertex
B
B
B
. Prove that
∠
A
B
C
≤
6
0
o
\angle ABC \le 60^o
∠
A
BC
≤
6
0
o
geometry
geometric inequality
angles