Points on a Circle
_I/ X \__
/ | \
/ M \
/ | \
\ | /
\ N /
\_J | __/
Demonstrate that I, J, K are on the same straight line.
Given a circle (c) with center O and diameters X'OX and Y'OY
perpendicular to each other.
M is the middle of OX.
The circle of center M and radius MY cuts OX' at N.
The circle of center Y and radius YN cuts (c) at I and J.
The perpendicular from M to YN cuts OY at K.
Hint: with this problem, there are two ways of drawing a regular pentagon
within a circle.
Source: Reader Philippe Fondanaiche's personal wording from different books
on how to draw a regular pentagon within a given circle.
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