# Geogebra resources

Geogebra is a fantastic free piece of software you can use to enhance your pupils’ learning. It combines the ability of graph-plotting with dynamic geometry. Think of it as Omnigraph and The Geometer’s Sketchpad in one program that is much easier to use, more intuitive and looks a lot better!

For a great series of tutorials on how to get up to speed with Geogebra check out the Mathematics and Multimedia Gegebra Step-By-Step Tutorial Series.

If you haven’t time to learn how to create your own teaching resources in Geogebra, but would like to use some of mine, please feel free to click on them below:

### Angle Theorems

Angles around a point add to 360 degrees

Angles on a straight line add up to 180 degrees

Angles in a triangle add up to 180 degrees

Vertically opposite angles are equal

In parallel lines corresponding angles are equal

In parallel lines alternate angles are equal

In parallel lines interior angles add up to 180 degrees

Angles in parallel lines investigation

### Circle Theorems

Angles in a semicircle are 90 degrees

Angles in the same segment are equal

The angle subtended at the centre of a circle is double the size of the angle subtended at the edge from the same two points

The perpendicular from the centre to the chord bisects the chord

The angle between the tangent and radius is 90 degrees

Tangents from a point outside the circle are equal in length

Alternate segment theorem

### Linear Equations and Straight Line Graphs

Effect of m and c coefficients on a graph of y = mx + c