Geometric Drawings and Constructions

Video lessons without Words

Croatian version 

Here you can find videos that show geometric drawings and constructions on paper or in GeoGebra.

Thanks to Rex Boggs, Rockhampton Grammar School, Australia (http://bit.ly/rexboggs) for help with the English translation.

Topics:

>  Parallel Lines

>  Perpendicular Lines

>  Angles

>  Dividing Line Segment

>  Constructing Triangles

>  Circumcircle and Inscribed Circle of the Triangle Construction

Explanations of the terms "drawing", "construction" and "sketch":

Drawing

When we draw (in geometry) then we are allowed to use a range of geometric tools such as a triangle, straightedge, ruler, compass and a protractor.

Construction

When we construct, we are only allowed to use a compass and/or a straightedge. Measuring using a ruler or a triangle is not allowed. Transferring a distance or a length can be done with a compass.

Sketch

To sketch means to draw without any geometrical equipment, using just a pencil. We can sketch when it's not important to have a precise drawing.