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Interactive version of Maths Theorem 19

NEWS / 22 March 2012

Ms. McCarthy has created an interactive version of Theorem 19 (the angle at the centre is twice the angle at the arc) using GeoGebra. GeoGebra is free mathematics software to create interactive graphics, algebra and spreadsheets.

Theorem: The angle at the centre is twice the angle at the arc

Theorem 19: The angle at the centre of a circle standing on a given arc is twice the angle at any point of the circle standing on the same arc.

Instructions: Move the angle on the arc around using the mouse, keeping it on the circle and you will note the value of the angle is always half the angle at the centre. Similarily if you change the value of the angle at the centre the angle on the arc changes.

NOTE: If you do not see an interactive  mathematical diagram, created with GeoGebra, you must download Java software so that your browser can display it correctly. Go to the Java website now and click the 'download now' button! It should take about 5 minutes for you install.

This is a Java Applet created using GeoGebra from www.geogebra.org - it looks like you don't have Java installed, please go to www.java.com

 

Ms. McCarthy, Created with GeoGebra

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