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Transformation
The following examples describe some basic geometric transformations in Geogebra. We show the steps for reflecting or rotating an inserted picture. The same procedures can be applied to other geometric objects such as points or polygons.
Reflection of a figure
Step 1: Insert a picture
Step 2: Reflect the picture in a line
Example 1 for reflection
Example 2 for reflection
Rotation of a figure, with a fixed angle
Step 1: Insert a picture, the same step in the example above
Step 2: Rotate the picture about a point by 90 degrees
Example 1 for rotation
Rotation of a figure, by a variable angle
Step 1: Insert a picture, the same step in the example above
Step 2: Create an angle
Step 3: Rotate the picture by the marked angle
Example 2 for rotation
Example 3 for rotation
The following examples show two regular pentagons constructed by using rotating points with given angles. Study the construction protocols to find how they can be done.
Regular pentagon on a given side
Regular pentagon with a given center