MathDB
Problems
Contests
National and Regional Contests
Russia Contests
All-Russian Olympiad
1990 All Soviet Union Mathematical Olympiad
515
515
Part of
1990 All Soviet Union Mathematical Olympiad
Problems
(1)
ASU 515 All Soviet Union MO 1990 abc = a'b'c' = a"b"c", lengths of segments
Source:
8/14/2019
The point
P
P
P
lies inside the triangle
A
B
C
ABC
A
BC
. A line is drawn through
P
P
P
parallel to each side of the triangle. The lines divide
A
B
AB
A
B
into three parts length
c
,
c
′
,
c
"
c, c', c"
c
,
c
′
,
c
"
(in that order), and
B
C
BC
BC
into three parts length
a
,
a
′
,
a
"
a, a', a"
a
,
a
′
,
a
"
(in that order), and
C
A
CA
C
A
into three parts length
b
,
b
′
,
b
"
b, b', b"
b
,
b
′
,
b
"
(in that order). Show that
a
b
c
=
a
′
b
′
c
′
=
a
"
b
"
c
"
abc = a'b'c' = a"b"c"
ab
c
=
a
′
b
′
c
′
=
a
"
b
"
c
"
.
geometry
Segment
Product