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Basic Constructions
This page contains information about basic construction techniques. Click the file icons on the right to open individual viewlets.

Geometric figures are constructed from basic elements such as points, lines (including segments and rays and circles.
Free points can be dragged around without restriction while points on objects (lines or circles) have their movement restricted on the parent objects. Points are also created as intersections of objects.
Lines and circles are defined by points. On the other hand, intersections of lines and circles define new points.

Try some free-hand drawing and get familiar with the tools and the behaviour of objects.
Use 'Construct' menu for specific constructions or shortcuts, such as parallel and perpendicular lines, midpoints, angle bisectors. These commands are available in most dynamic geometry software and are important tools for euclidean constructions. I call them 'shortcuts' because basically they can be obtained through lines and circles constructions (i.e., straightedge and compass constructions).
Simple Measurement and Calculation
measure length of segment and distance between points
measure area of triangle and other polygon (interiors)
measure circle (radius, circumference and area) and calculate ratio
measure angle and calculate ratio
Tools for Investigations
Trace a point while it moves, this option can show temporarily a locus of a point.
Split/Merge a point from/to a path (a line or a circle)