# Dynamic Geometry Problem 1466: Tangential Quadrilateral, Newton Line, Incenter,
Midpoint, Diagonal, Collinear Points.

Let ABCD be a tangential quadrilateral and O be the center of the inscribed circle (see the figure below). if M and N are the midpoints of the diagonals AC and BD, prove that M, O, and N are collinear points..

### Newton Line

Newton line is the line that connects the midpoints of the two diagonals in a quadrilateral other than a
parallelogram.

### Tangential Quadrilateral

Tangential quadrilateral or circumscribed quadrilateral is a convex quadrilateral whose sides are all tangent to a circle
inside it.

## Static Diagram of Geometry Problem 1466

## Poster of Geometry Problem 1466 using iPad Apps

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Classroom Resource:

Interactive step-by-step animation using GeoGebra

This step-by-step interactive illustration was created with
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### Recent Additions

Geometry Problems

Open Problems

Visual Index

Ten problems: 1411-1420

All Problems

Quadrilateral

Tangential or Circumscribed Quadrilateral

Incenter, Inscribed circle

Circle

Circle Tangent Line

Midpoint

Collinear Points

Newton-Gauss Line

Dynamic Geometry

GeoGebra

HTML5 and Dynamic Geometry

iPad Apps

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