If a points ,
, and
are marked on each side of a triangle
, one on each side (or on a side's
extension), then the three Miquel circles (each
through a polygon vertex and the two marked points
on the adjacent sides) are concurrent at a point
called the Miquel
point. This result is a slight generalization of the so-called pivot
theorem.
If
lies in the interior of the triangle, then it satisfies
(1)
| |||
(2)
| |||
(3)
|
The lines from the Miquel point to the marked points make equal angles with the respective sides. (This is a by-product of the Miquel equation.)
A generalized version of Miquel's theorem states that given four lines , ...,
each intersecting the other
three, the four Miquel circles passing through
each subset of three intersection points of the lines meet in a point known as the
4-Miquel point
.
Furthermore, the centers of these four Miquel circles
lie on a circle
(Johnson 1929, p. 139). The lines from
to given points on the sides make equal angles
with respect to the sides.
Moreover, given
lines taken by
s
yield
Miquel circles like
passing through a point
, and their centers lie on a circle
.