MathDB

_|_ planes wanted, regular pyramid 1999 Romania NMO VIII p4

Source:

August 14, 2024

geometry3D geometrypyramid

Problem Statement

Let

SABC

be a regular pyramid,

O

the center of basis

ABC

, and

M

the midpoint of

[BC]

. If

N \in [SA]

such that

SA = 25 \cdot NS

and

SO \cap MN=\{P\}

AM=2\cdot SO

, prove that the planes

(ABP)

and

(SBC)

are perpendicular.