MathDB
Problems
Contests
National and Regional Contests
Spain Contests
pOMA and PErA mathematical olympiads
2024 PErA
P2
P2
Part of
2024 PErA
Problems
(1)
Locus of pastanaga points
Source: PErA 2024/2
3/4/2024
Let
A
B
C
D
ABCD
A
BC
D
be a fixed convex quadrilateral. Say a point
K
K
K
is pastanaga if there's a rectangle
P
Q
R
S
PQRS
PQRS
centered at
K
K
K
such that
A
∈
P
Q
,
B
∈
Q
R
,
C
∈
R
S
,
D
∈
S
P
A\in PQ, B\in QR, C\in RS, D\in SP
A
∈
PQ
,
B
∈
QR
,
C
∈
RS
,
D
∈
SP
. Prove there exists a circle
ω
\omega
ω
depending only on
A
B
C
D
ABCD
A
BC
D
that contains all pastanaga points.
geometry
rectangle